agent: TodosPanel/InboxPanel flyouts + header pills

New Preact `SidePanel` drawer — deliberately not the shared
`<hive-side-panel>` shadow-DOM custom element, same rationale as
StatusChips' Badge/Dropdown. Drops that element's drag-to-resize +
localStorage width persistence for this first slice (fixed width via
CSS); reuses agent.css's existing `.agent-inbox`/`.inbox-*`/
`.side-panel-empty` content classes verbatim, only the drawer chrome
itself is new (SidePanel.css). Kept mounted regardless of open/closed
state (toggles the `open` prop) rather than conditionally rendered, so
the slide/fade CSS transitions actually fire on both open and close.

- InboxPanel: renders `state.inbox` (already polled by useAgentState)
  + a "mark all read" action — plain `fetch()` to the dashboard's
  `/api/agent/{name}/mark-all-read` (JSON response, same as app.js;
  unlike pause/resume this one doesn't need a form-submit workaround).
- TodosPanel: new `useTodos` hook (same 4s poll cadence as app.js's
  `refreshTodos`) + bulk select/mark-done via `api/todos/mark-done`.
- Both destructive-but-recoverable actions use a new `useConfirmClick`
  two-click-arm hook instead of the old shadow-DOM `themedConfirm`
  modal — lighter weight, no backdrop/dialog machinery needed for a
  "did you mean to click that" nudge.
- HeaderPill: the inbox/todos count triggers in the header's right
  cluster; Header.tsx gained a `pills` slot for them (mirrors the old
  markup's `.agent-header-pills` third column).
- types.ts: added `InboxRow`/`TodoRow`, mirroring
  `hive_sh4re::inbox::{InboxRow, LooseEnd}` (todo variant only —
  `/api/todos` never returns the others).

Screenshot-verified against a mock server exercising both panels.

frontend/packages/agent/src/components/Header.tsx

@@ -14,9 +14,13 @@ export interface HeaderProps {
   label: string;
   hiveLabel?: string | null;
   children?: ComponentChildren;
+  /** Right-cluster flyout triggers (inbox/todos pills today, the
+   * overflow menu button lands here in a later commit) — mirrors the
+   * old markup's `.agent-header-pills` third column. */
+  pills?: ComponentChildren;
 }
 
-export function Header({ label, hiveLabel, children }: HeaderProps) {
+export function Header({ label, hiveLabel, children, pills }: HeaderProps) {
   return (
     <header class="agent-header">
       <img class="agent-icon" src="icon" alt="" />
@@ -27,6 +31,7 @@ export function Header({ label, hiveLabel, children }: HeaderProps) {
         {hiveLabel ? <div class="agent-header-row agent-hive-row">{hiveLabel}</div> : null}
         <div class="agent-header-row">{children}</div>
       </div>
+      {pills ? <div class="agent-header-pills">{pills}</div> : null}
     </header>
   );
 }

frontend/packages/agent/src/components/HeaderPill.tsx

@@ -0,0 +1,26 @@
+// <HeaderPill> — the inbox/todos flyout triggers in the header's right
+// cluster. Reuses agent.css's existing `.hive-pill.header-pill…` rules
+// (loaded globally) — same "layout is a like-for-like port, the
+// component model is the change" approach as Header.tsx. Hidden
+// (renders nothing) at count 0, matching the old page's `pill.hidden =
+// count === 0`.
+export interface HeaderPillProps {
+  kind: 'inbox' | 'todos';
+  icon: string;
+  label: string;
+  count: number;
+  onClick: () => void;
+}
+
+export function HeaderPill({ kind, icon, label, count, onClick }: HeaderPillProps) {
+  if (count === 0) return null;
+  return (
+    <button type="button" class={`hive-pill header-pill header-pill-${kind}`} onClick={onClick} title={`open ${label} flyout`}>
+      <span class="header-pill-icon" aria-hidden="true">
+        {icon}
+      </span>
+      <span class="header-pill-label">{label}</span>
+      <span class="header-pill-count">{count}</span>
+    </button>
+  );
+}

frontend/packages/agent/src/components/InboxPanel.tsx

@@ -0,0 +1,86 @@
+// <InboxPanel> — content rendered inside <SidePanel> for the inbox
+// flyout. "mark all read" POSTs to the *dashboard's* origin (not this
+// agent's own backend) via a plain `fetch()`, same as app.js's
+// `buildInboxMarkAllRow` — unlike pause/resume this one's fine as a
+// fetch even when the two are genuinely cross-origin, because
+// `hive-c0re`'s `/api/agent/{name}/mark-all-read` route replies with
+// JSON, not a redirect; in the common gateway-fronted deployment
+// `dashboardBase` already resolves to `location.origin` anyway (see
+// dashboardBase.ts), so it's same-origin in practice.
+import { useState } from 'preact/hooks';
+import { useConfirmClick } from '../lib/useConfirmClick.js';
+import type { InboxRow } from '../types.js';
+
+export interface InboxPanelProps {
+  rows: InboxRow[];
+  label: string;
+  dashboardBase: string;
+  onCleared: () => void;
+}
+
+function fmtTs(unixSeconds: number): string {
+  return new Date(unixSeconds * 1000).toISOString().replace('T', ' ').slice(5, 19);
+}
+
+export function InboxPanel({ rows, label, dashboardBase, onCleared }: InboxPanelProps) {
+  const [status, setStatus] = useState('');
+  const [busy, setBusy] = useState(false);
+
+  async function markAllRead() {
+    if (!dashboardBase || !label) {
+      setStatus('dashboard url / label unknown');
+      return;
+    }
+    setBusy(true);
+    setStatus('clearing…');
+    try {
+      const resp = await fetch(`${dashboardBase}api/agent/${encodeURIComponent(label)}/mark-all-read`, {
+        method: 'POST',
+      });
+      if (resp.ok) {
+        const data = await resp.json().catch(() => ({}));
+        const n = Number((data as { marked?: number }).marked) || 0;
+        setStatus(`✓ marked ${n} as read`);
+        onCleared();
+      } else {
+        setStatus(`failed: http ${resp.status}`);
+      }
+    } catch (err) {
+      setStatus(`failed: ${err instanceof Error ? err.message : String(err)}`);
+    } finally {
+      setBusy(false);
+    }
+  }
+
+  const { armed, trigger } = useConfirmClick(markAllRead);
+
+  if (!rows.length) {
+    return <p class="side-panel-empty">inbox empty.</p>;
+  }
+
+  return (
+    <div class="agent-inbox">
+      <div class="inbox-mark-all-row">
+        <button
+          type="button"
+          class="inbox-mark-all-btn"
+          onClick={trigger}
+          disabled={busy}
+          title="mark every queued message for this agent as read — drains the host broker's pending + delivered-unacked rows. history shown here is the most-recent-N regardless of state, so the list itself stays visible."
+        >
+          {armed ? 'sure? click again' : '✓ mark all read'}
+        </button>
+        <span class="inbox-mark-status">{status}</span>
+      </div>
+      <ul>
+        {rows.map((m) => (
+          <li key={m.id} class={m.in_reply_to != null ? 'inbox-reply' : undefined}>
+            {m.in_reply_to != null && <span class="inbox-reply-tag">↳ reply · </span>}
+            <span class="inbox-ts">{fmtTs(m.at)}</span> <span class="inbox-from">{m.from}</span>{' '}
+            <span class="inbox-sep">→</span> <span class="inbox-body">{m.body}</span>
+          </li>
+        ))}
+      </ul>
+    </div>
+  );
+}

frontend/packages/agent/src/components/SidePanel.css

@@ -0,0 +1,80 @@
+/* Drawer chrome for <SidePanel> — backdrop, drawer box, header, close
+   button. Content styling (.agent-inbox, .inbox-*, .side-panel-empty)
+   already ships globally via agent.css; the two rules at the bottom
+   here re-target agent.css's old `hive-side-panel .agent-inbox …`
+   flatten-when-inside-a-panel overrides at this component's own class
+   instead, since this is a plain Preact tree, not a custom element. */
+.agent-side-panel-backdrop {
+  position: fixed;
+  inset: 0;
+  background: rgba(0, 0, 0, 0.5);
+  z-index: 60;
+  opacity: 0;
+  pointer-events: none;
+  transition: opacity 160ms ease;
+}
+.agent-side-panel-backdrop.open {
+  opacity: 1;
+  pointer-events: auto;
+}
+.agent-side-panel-drawer {
+  position: fixed;
+  top: 0;
+  right: 0;
+  bottom: 0;
+  width: min(26em, 96vw);
+  background: var(--bg-elev);
+  border-left: 1px solid var(--border);
+  box-shadow: -8px 0 24px rgba(0, 0, 0, 0.4);
+  z-index: 61;
+  display: flex;
+  flex-direction: column;
+  transform: translateX(100%);
+  transition: transform 200ms ease;
+}
+.agent-side-panel-drawer.open {
+  transform: translateX(0);
+}
+.agent-side-panel-head {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  padding: 0.6em 0.8em;
+  border-bottom: 1px solid var(--border);
+  color: var(--fg);
+}
+.agent-side-panel-title {
+  font-weight: bold;
+  letter-spacing: 0.03em;
+}
+.agent-side-panel-close {
+  background: none;
+  border: 0;
+  color: var(--muted);
+  font-size: 1.1em;
+  line-height: 1;
+  cursor: pointer;
+  padding: 0.3em 0.5em;
+  min-width: 2.75em;
+  min-height: 2.75em;
+}
+.agent-side-panel-close:hover {
+  color: var(--fg);
+}
+.agent-side-panel-body {
+  flex: 1;
+  overflow-y: auto;
+  padding: 0.8em;
+}
+.agent-side-panel-body .agent-inbox {
+  margin: 0;
+  font-size: inherit;
+  color: var(--fg);
+}
+.agent-side-panel-body .agent-inbox ul {
+  background: transparent;
+  border-left: 0;
+  padding: 0;
+  max-height: none;
+  overflow: visible;
+}

frontend/packages/agent/src/components/SidePanel.tsx

@@ -0,0 +1,55 @@
+// <SidePanel> — the slide-in drawer for the inbox/todos flyouts.
+// Deliberately a new Preact component, not the shared
+// `<hive-side-panel>` shadow-DOM custom element (@hive/shared/
+// side-panel.js) — same rationale as StatusChips' Badge/Dropdown:
+// mara's ask was real Preact components for this rewrite, not a port
+// of the old widget family. Drops that element's drag-to-resize +
+// localStorage width persistence for this first slice (fixed width via
+// CSS, see SidePanel.css) — a real simplification, not an oversight;
+// revisit if a fixed width proves cramped in practice.
+//
+// Content styling (`.agent-inbox`, `.inbox-*`, `.side-panel-empty`)
+// already ships globally via `agent.css` and is reused verbatim by
+// InboxPanel/TodosPanel — only the drawer chrome itself is new here.
+import { useEffect } from 'preact/hooks';
+import type { ComponentChildren } from 'preact';
+import './SidePanel.css';
+
+export interface SidePanelProps {
+  open: boolean;
+  title: string;
+  onClose: () => void;
+  children?: ComponentChildren;
+}
+
+export function SidePanel({ open, title, onClose, children }: SidePanelProps) {
+  useEffect(() => {
+    if (!open) return;
+    function onKey(e: KeyboardEvent) {
+      if (e.key === 'Escape') onClose();
+    }
+    document.addEventListener('keydown', onKey);
+    return () => document.removeEventListener('keydown', onKey);
+  }, [open, onClose]);
+
+  return (
+    <>
+      <div class={`agent-side-panel-backdrop${open ? ' open' : ''}`} onClick={onClose} aria-hidden="true" />
+      <aside
+        class={`agent-side-panel-drawer${open ? ' open' : ''}`}
+        role="dialog"
+        aria-modal="true"
+        aria-hidden={!open}
+        aria-label={title}
+      >
+        <div class="agent-side-panel-head">
+          <span class="agent-side-panel-title">{title}</span>
+          <button type="button" class="agent-side-panel-close" title="close (esc)" onClick={onClose}>
+            ✕
+          </button>
+        </div>
+        <div class="agent-side-panel-body">{children}</div>
+      </aside>
+    </>
+  );
+}

frontend/packages/agent/src/components/TodosPanel.tsx

@@ -0,0 +1,104 @@
+// <TodosPanel> — content rendered inside <SidePanel> for the todos
+// flyout. "mark done" POSTs to this agent's own backend
+// (`api/todos/mark-done`, same-origin), unlike InboxPanel's cross-agent
+// mark-all-read.
+import { useState } from 'preact/hooks';
+import type { TodoRow } from '../types.js';
+
+export interface TodosPanelProps {
+  todos: TodoRow[];
+  onCleared: () => void;
+}
+
+function fmtAge(seconds: number): string {
+  if (seconds < 60) return `${seconds}s`;
+  if (seconds < 3600) return `${Math.floor(seconds / 60)}m`;
+  if (seconds < 86400) return `${Math.floor(seconds / 3600)}h`;
+  return `${Math.floor(seconds / 86400)}d`;
+}
+
+export function TodosPanel({ todos, onCleared }: TodosPanelProps) {
+  const [checked, setChecked] = useState<Set<number>>(new Set());
+  const [status, setStatus] = useState('');
+  const [busy, setBusy] = useState(false);
+
+  function toggle(id: number) {
+    setChecked((prev) => {
+      const next = new Set(prev);
+      if (next.has(id)) next.delete(id);
+      else next.add(id);
+      return next;
+    });
+  }
+
+  async function markDone() {
+    const ids = [...checked];
+    if (!ids.length) return;
+    setBusy(true);
+    setStatus('marking…');
+    try {
+      const resp = await fetch('api/todos/mark-done', {
+        method: 'POST',
+        headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
+        body: `ids=${encodeURIComponent(ids.join(','))}`,
+      });
+      if (resp.ok) {
+        setStatus('✓ marked done');
+        setChecked(new Set());
+        onCleared();
+      } else {
+        setStatus(`failed: ${await resp.text()}`);
+      }
+    } catch (err) {
+      setStatus(`failed: ${err instanceof Error ? err.message : String(err)}`);
+    } finally {
+      setBusy(false);
+    }
+  }
+
+  if (!todos.length) {
+    return <p class="side-panel-empty">no todos — all subsystem queues are clear.</p>;
+  }
+
+  const allChecked = todos.length > 0 && todos.every((t) => checked.has(t.id));
+
+  return (
+    <div class="agent-inbox">
+      <div class="inbox-mark-all-row">
+        <button
+          type="button"
+          class="inbox-mark-all-btn"
+          onClick={() => setChecked(allChecked ? new Set() : new Set(todos.map((t) => t.id)))}
+        >
+          {allChecked ? 'select none' : 'select all'}
+        </button>
+        <button type="button" class="inbox-mark-all-btn" onClick={markDone} disabled={busy || checked.size === 0}>
+          ✓ mark done
+        </button>
+        <span class="inbox-mark-status">{status}</span>
+      </div>
+      <ul>
+        {todos.map((t) => {
+          const cbId = `todo-cb-${t.id}`;
+          const label = t.source ? `${t.subsystem} · ${t.source}` : t.subsystem;
+          return (
+            <li key={t.id}>
+              <input
+                type="checkbox"
+                id={cbId}
+                class="todo-cb"
+                checked={checked.has(t.id)}
+                onChange={() => toggle(t.id)}
+              />{' '}
+              <label for={cbId} class="inbox-from">
+                {label}
+              </label>{' '}
+              <span class="inbox-ts">{fmtAge(t.age_seconds)} ago</span>
+              <div class="inbox-body">{t.summary}</div>
+            </li>
+          );
+        })}
+      </ul>
+    </div>
+  );
+}