chore(agent): track .agent/ planning tree in git

Remove the blanket .agent/ gitignore so the phase roadmap, user
stories, reports, and PLAN.md are versioned with the code. Only
runtime artifacts (.agent/phase-sessions/, .agent/pipeline.log)
remain ignored. Update AGENTS.md git protocol rule to match.

.agent/phases/complete/06_story_loading_feedback/00_phase.md

@@ -0,0 +1,64 @@
+# Phase 06 — Story: Loading Feedback & Progress
+
+**Story:** `.agent/user_stories/loading-feedback.md`
+**Context:** `.agent/PLAN.md` §7.4 ("never stale" contract), §9
+
+## Goal
+An unambiguous state machine — `idle → thinking → streaming → done |
+error → idle` — so the user always knows what's happening, and a stale
+Send button is impossible.
+
+## Implementation steps
+1. `app.js` — formalize the state machine (single `setUiState(state)`
+   function driving: typing indicator, send button disabled/spinner/label,
+   `#send-status` live text). Replace ad-hoc busy handling from Phase 03.
+2. Pre-token: typing indicator (`role="status"`,
+   `aria-label="Brain of Reese is thinking"`); after 10s pre-token, update
+   the label with elapsed seconds (setInterval, cleared on state change).
+3. Streaming: first `delta` removes the typing indicator and starts
+   appending to the answer bubble; button stays busy.
+4. Error paths: `{"type":"error"}` SSE event, non-2xx response, or
+   **120s client-side timeout** (clear on first delta) → red banner
+   `role="alert"` ("Try again — if this persists, check the LLM is
+   reachable") + state → idle.
+5. `prefers-reduced-motion`: CSS already slows animations — verify; add a
+   static fallback for the dots if needed.
+6. Server: confirm the per-turn log line includes `embed_ms` and
+   `total_ms` (add if Phase 03 omitted it).
+
+## UI Verification
+Walk the full state machine by hand (dev server + mock LLM slow path):
+submit → indicator + "Thinking…" disabled button → live tokens → done
+(enabled, focused input). Kill the mock mid-stream → banner + recovery.
+Contrast of disabled button + spinner OK; reduced-motion pass.
+
+## Testing & Quality
+- Unit/integration: SSE error event serialization; timeout constant
+  exported/testable; (JS logic is E2E-covered).
+- Coverage: **>90%** on `app/`.
+
+## Playwright Execution Phase
+Run ONLY this story's suite:
+
+```bash
+uv run pytest tests/e2e/test_loading_feedback.py -v --no-cov
+```
+
+Implements the story mapping (mock LLM's 3s "pretend to think slowly"
+warm-up + a fixture that stops the mock): typing indicator visible during
+pre-token and gone by answer; button disabled→"Thinking…"→enabled "Send";
+streaming appends (two-timestamp length check); LLM-down ⇒ `role=alert`
+banner + button recovered.
+
+## Success criteria
+- [ ] every in-flight state has a visible indicator; button never zombies
+- [ ] error + 120s timeout paths both recover cleanly
+- [ ] reduced-motion respected
+- [ ] unit + integration green, coverage >90%
+- [ ] story E2E green in isolation
+- [ ] committed
+
+## Commit
+```bash
+git add -A && git commit --no-gpg-sign -m "feat(ui): explicit chat state machine — typing indicator, streaming progress, timeout and error recovery"
+```