docs: turn_stats sink + event-driven agent badges + dashboard event vocabulary

docs/web-ui.md

@@ -201,6 +201,22 @@ not ours.
   a managed container.
 - `GET /api/agent-config/{name}` — read-only view of the applied
   `agent.nix`.
+- `GET /api/state-file?path=<host-or-container-path>` — bounded
+  text read of a file under the per-agent `state/` subtree or
+  the shared `/var/lib/hyperhive/shared/`. Accepts the
+  container-view forms (`/agents/<n>/state/...`, `/shared/...`)
+  and the host form. Canonicalises + verifies the path stays
+  inside the allow-list, refuses anything but a regular file,
+  refuses `/agents/<n>/claude` / `config` subtrees, truncates
+  bodies at 1 MiB. Backs the dashboard's inline path-link
+  preview (PATH_RE detects pointer strings in message bodies,
+  question/answer text, and the operator inbox; clicking
+  expands a `<details>` that lazy-fetches via this endpoint).
+  Trailing-slash matches (i.e. directory paths) are skipped on
+  the client side — only files linkify.
+- `GET /api/reminders` — list pending reminders for the
+  dashboard's queued-reminders panel.
+- `POST /cancel-reminder/{id}` — hard-delete a pending reminder.
 - `GET /dashboard/stream` — unified live event channel:
   broker `sent` / `delivered`, plus the mutation events listed
   below. Each frame carries `seq`.
@@ -223,21 +239,37 @@ payload):
   queue + history mutations. Client mutates a derived store and
   re-renders only the approvals section.
 - `question_added` (id, asker, question, options, multi,
-  asked_at, deadline_at) / `question_resolved` (id, answer,
-  answerer, answered_at, cancelled) — operator-targeted
-  questions only (peer-to-peer questions never fire these). The
-  ttl watchdog fires `question_resolved` with
-  `answerer = "ttl-watchdog"` on expiry.
+  asked_at, deadline_at, target) / `question_resolved` (id,
+  answer, answerer, answered_at, cancelled, target) — both
+  operator-targeted and peer (agent-to-agent) threads fire
+  these. The dashboard's questions pane surfaces both, with
+  filter chips (all / @operator / @peer / per-participant) and
+  an `0V3RR1D3` button on peer rows so the operator can
+  answer when an agent is stuck. The ttl watchdog fires
+  `question_resolved` with `answerer = "ttl-watchdog"` on
+  expiry.
 - `transient_set` (name, transient_kind, since_unix) /
   `transient_cleared` (name) — lifecycle action spinners. The
   client ticks the elapsed-seconds badge off `since_unix`
   client-side, no polling.
+- `container_state_changed` (container: ContainerView) /
+  `container_removed` (name) — per-row container mutations,
+  emitted by `Coordinator::rescan_containers_and_emit` from
+  every mutation site (`actions::approve` post-spawn,
+  `actions::destroy`, the lifecycle_action wrapper,
+  `auto_update::rebuild_agent`) and from the 10s
+  `crash_watch` poll. Client upserts/removes by name; the
+  pending overlay is read from `transientsState` since the
+  payload doesn't carry it.
 
-`/api/state` still serves `approvals` / `approval_history` /
-`questions` / `question_history` / `transients` for cold-start
-on first page load and as a safety-net resync from the 5s poll;
-the client maintains the same arrays in derived stores and
-applies the events on top.
+`/api/state` is **only fetched on cold-load and on the few
+forms that mutate non-event-derived state** (PURG3 +
+meta-update, since tombstones + meta_inputs aren't event-
+shaped yet). Every other section — approvals, questions,
+transients, containers, operator inbox, message flow —
+derives from `/dashboard/stream` after the initial snapshot,
+maintaining its own client-side store and applying events on
+top. The 5s periodic poll is gone.
 
 Generalised form helpers: `form[data-confirm="…"]` pops
 `confirm()` before submit; `form[data-prompt="…"]` pops
@@ -250,16 +282,34 @@ Layout, top to bottom:
 
 - Banner (gradient shimmer while state=thinking).
 - Title with `↑ DASHB04RD` back-link (new tab) + `↻ R3BU1LD`.
-- Status section (online / needs login / login-in-progress).
-- **State row**: state badge + model chip + last-turn timing +
-  cancel-turn button + new-session button.
+- Status section: empty when online (alive-badge in the state
+  row carries the signal), populated with the login form /
+  OAuth URL when `status` is `needs_login_*`.
+- **State row**: alive badge + state badge + model chip + ctx
+  badge + last-turn timing + cancel-turn button + new-session
+  button. Every chip carries a `title=...` tooltip with the
+  detailed breakdown.
+  - Alive badge: `● alive` (green) / `◌ needs login` (amber) /
+    `◌ logging in` / `○ offline` / `… connecting`. Driven by
+    `LiveEvent::StatusChanged`; replaces the old "harness alive
+    — turn loop running" paragraph so the state row carries
+    every reachability signal.
   - State badge: `💤 idle` / `🧠 thinking` / `📦 compacting` /
     `○ offline` / `… booting`, with an age suffix (`12s`,
-    `2m 14s`). Driven from `/api/state.turn_state` +
-    `turn_state_since`; SSE turn_start/turn_end still flip it
-    instantly between polls. Authoritative source is the
-    harness's `Bus::state_snapshot()`.
-  - Model chip: `model · <name>` (e.g. `model · haiku`).
+    `2m 14s`). Driven by `LiveEvent::TurnStateChanged`
+    (`{state, since_unix}`) — the bus emits on every
+    `Bus::set_state` so the badge updates without a /api/state
+    refetch. Cold-load via `/api/state.turn_state` +
+    `turn_state_since`.
+  - Model chip: `model · <name>` (e.g. `model · haiku`). Driven
+    by `LiveEvent::ModelChanged`; emitted from `Bus::set_model`.
+  - Ctx badge: `ctx · 142k` — total prompt tokens in the
+    current context window (input + cache_read + cache_write),
+    mirroring claude code's bottom-right indicator. Hover for
+    the breakdown including output. Driven by
+    `LiveEvent::TokenUsageChanged`; emitted from
+    `Bus::record_usage` whenever the terminal `result` event
+    delivers a fresh usage block.
   - Last-turn chip: `last turn 12.3s` appears after the first
     turn ends, computed from the state-since deltas.
   - `■ cancel turn` button: visible only while state=thinking,
@@ -269,6 +319,11 @@ Layout, top to bottom:
     arm a one-shot Bus flag — the next turn drops
     `--continue`, starting a fresh claude session. Subsequent
     turns resume normal `--continue`.
+
+  Polling: `/api/state` is fetched **once** on cold load, and
+  again while `status === 'needs_login_in_progress'` (login
+  session output isn't event-shaped yet). Every other badge
+  updates from SSE; no periodic refresh timer runs.
 - Inbox `<details>` block (collapsed): `inbox · N` — last 30
   messages addressed to this agent, fetched via
   `AgentRequest::Recent { limit: 30 }`. (Separate from
@@ -345,14 +400,38 @@ Unknown `/foo` shows an error row instead of being silently sent.
 
 ### Per-agent endpoints
 
+All POSTs return 200 (no 303 redirects). The matching mutations
+fire `LiveEvent` variants on the per-agent bus, so the client
+doesn't refetch `/api/state` on submit — the SSE stream
+delivers the new state faster anyway. Only the login flow still
+polls (session output streams in updates that aren't event-
+shaped).
+
 - `POST /send` — operator-injected message into this agent's inbox.
 - `POST /login/{start,code,cancel}` — claude OAuth login flow.
-- `POST /api/cancel` — SIGINT the in-flight claude turn.
+  Start/cancel emit `LiveEvent::StatusChanged` to flip the
+  badge to/from `needs_login_in_progress`.
+- `POST /api/cancel` — SIGINT the in-flight claude turn. Emits a
+  `LiveEvent::Note`.
 - `POST /api/compact` — run `/compact` on the persistent session
   (same MCP config + system prompt + allowed tools as a normal
-  turn — only the stdin payload differs).
+  turn — only the stdin payload differs). Flips state to
+  `Compacting` via `Bus::set_state`, which emits
+  `TurnStateChanged`.
 - `POST /api/model` (`model=<name>`) — switch the model for
-  future turns.
+  future turns. `Bus::set_model` emits `ModelChanged`.
 - `POST /api/new-session` — arm a one-shot for the next turn to
-  drop `--continue`.
+  drop `--continue`. Emits a `LiveEvent::Note`.
 - `GET /events/history` — replay buffer for the terminal.
+
+Bus events (new vocabulary on `/events/stream`):
+
+- `status_changed { status }` — `online` /
+  `needs_login_idle` / `needs_login_in_progress`. Drives the
+  alive-badge.
+- `model_changed { model }` — drives the model chip.
+- `token_usage_changed { usage: TokenUsage }` — drives the
+  ctx-badge. Emitted from `Bus::record_usage` whenever the
+  stream-json `result` event delivers a fresh usage block.
+- `turn_state_changed { state, since_unix }` — drives the
+  state badge (`idle`/`thinking`/`compacting`).