swarm-ui: a schedules page, one card per scheduled prompt

/schedules lists the controller's scheduled prompts as cards: name as the
title, the agents it fires for, the message, its cadence and next fire.
Edit turns a card into its own form; pause, resume and remove act in place,
and + schedule opens an empty form. The form sends only what changed, so a
rename never moves the fire times, and warns when the start or the repeat
does. Filters reuse the shared card filter bar.

Adds a TextAreaField to the ui kit, and an upcoming mode on RelativeTime so
a next-fire time reads "in 5m". Needs the controller's /api/schedules
routes.

frontend/packages/swarm-ui/src/pages/schedules/ScheduleCard.tsx

@@ -0,0 +1,90 @@
+// <ScheduleCard> — one scheduled prompt as a card: its name as the title,
+// "agents: foo, bar" beneath, then the message, the cadence and when it
+// fires next. Edit, pause/resume and remove sit at the foot; edit swaps the
+// card for `ScheduleForm` (the page owns that swap).
+import { Badge, type BadgeTone } from "@hive/shared/badge.js";
+import { Button } from "../../ui/button/Button.js";
+import { Card } from "../../ui/card/Card.js";
+import { RelativeTime } from "../../ui/relative-time/RelativeTime.js";
+import {
+  fmtInterval,
+  fmtLocal,
+  scheduleState,
+  type Schedule,
+  type ScheduleState,
+} from "./ScheduleTypes.js";
+import "./ScheduleCard.css";
+
+const STATE_TONE: Record<ScheduleState, BadgeTone> = {
+  active: "positive",
+  paused: "warning",
+  done: "neutral",
+};
+
+export function ScheduleCard({
+  schedule,
+  pending,
+  onEdit,
+  onTogglePaused,
+  onRemove,
+}: {
+  schedule: Schedule;
+  /** A pause/resume or remove for this schedule is in flight. */
+  pending: boolean;
+  onEdit: () => void;
+  onTogglePaused: () => void;
+  onRemove: () => void;
+}) {
+  const state = scheduleState(schedule);
+  return (
+    <Card class="ui-schedule-card">
+      <div class="ui-schedule-card-head">
+        <h3 class="ui-schedule-card-name">{schedule.name}</h3>
+        <Badge tone={STATE_TONE[state]} value={state} />
+        <Badge
+          value={
+            schedule.interval_seconds === null
+              ? "once"
+              : `every ${fmtInterval(schedule.interval_seconds)}`
+          }
+        />
+      </div>
+      <div class="ui-schedule-card-agents">
+        agents: {schedule.agents.join(", ")}
+      </div>
+      <p class="ui-schedule-card-body">{schedule.body}</p>
+      <div class="ui-schedule-card-next">
+        {schedule.next_fire_unix !== null ? (
+          <>
+            next fire:{" "}
+            <span title={fmtLocal(schedule.next_fire_unix)}>
+              <RelativeTime epochMs={schedule.next_fire_unix * 1000} upcoming />
+            </span>
+          </>
+        ) : state === "paused" ? (
+          "paused, will not fire"
+        ) : (
+          <>
+            fired{" "}
+            <span title={fmtLocal(schedule.anchor_unix)}>
+              <RelativeTime epochMs={schedule.anchor_unix * 1000} />
+            </span>
+          </>
+        )}
+      </div>
+      <div class="ui-schedule-card-actions">
+        <Button onClick={onEdit} disabled={pending}>
+          edit
+        </Button>
+        {state !== "done" ? (
+          <Button onClick={onTogglePaused} disabled={pending}>
+            {schedule.paused ? "resume" : "pause"}
+          </Button>
+        ) : null}
+        <Button onClick={onRemove} disabled={pending}>
+          remove
+        </Button>
+      </div>
+    </Card>
+  );
+}