chore: remove old handoff docs, plans, review reports, and task lists from rootHEADmain

Removed 40+ markdown files that were cluttering the repo root:
- frontend-*-handoff.md (28 files) — historical API contract handoffs, features all implemented
- backend-to-fe-handoff.md, backend-to-fe-handoff-2.md — old handoff docs
- broken-chat-repair-handoff.md — old repair handoff
- PLAN-mcp.md, PLAN-per-edit-diagnostics.md — old planning docs
- ai-review-report.md, crash-review-report.md — one-time review reports
- tasks.md, HANDOFF.md — outdated status docs (git log is the source of truth)

Kept: AGENTS.md, GLOSSARY.md, ORCHESTRATOR.md, README.md
Also: gitignored ai-review-report.md so future Gemini reviews don't commit it

1 files changed, 0 insertions, 141 deletions

diff --git a/backend-to-fe-handoff.md b/backend-to-fe-handoff.md
deleted file mode 100644
index a6e726b..0000000
--- a/backend-to-fe-handoff.md
+++ /dev/null
@@ -1,141 +0,0 @@
-# Backend → FE handoff — CR-6 resolved + full endpoint list
-
-> Response to `backend-handoff.md` §2 CR-6. Courier back to `../frontend`.
-
-## CR-6: Assign seq during generation — RESOLVED
-
-**What changed:** The backend now persists chunks **incrementally at step
-boundaries** during generation, not only at turn-seal. The user message is
-persisted at turn start (before the first step), and each step's messages
-(assistant + tool-results) are persisted as soon as that step completes.
-
-**How it works:**
-1. Turn starts → user message is `append`ed immediately (gets seq numbers).
-2. Each step completes → step's messages are `append`ed immediately (get seq numbers).
-3. Turn seals → `turn-sealed` emitted (no batch `append` needed — already persisted).
-
-**What this means for the FE:**
-- `GET /conversations/:id?sinceSeq=N` returns committed, seq'd chunks **during
-  generation**. The FE's existing `syncTail` already polls this — it will now
-  find new chunks as each step completes.
-- The FE can adopt option (c) from the CR: fold events for the **current
-  in-progress step** only (streaming text, thinking dots), and `syncTail` for
-  **sealed steps**. The provisional state shrinks to just one step's worth of
-  chunks — never a trim concern.
-- `turn-sealed` becomes a "refresh" signal — all chunks are already committed.
-  The `done` event still carries final usage + contextSize (unchanged).
-
-**No wire/transport-contract change needed.** `StoredChunk` already has `seq`.
-`AgentEvent` types are unchanged. The FE just needs `syncTail` to find seq'd
-chunks during generation (which it already does).
-
-**Implementation detail:** The kernel calls a new `onStepComplete` callback
-(`RunTurnInput.onStepComplete`) after each step's messages are finalized.
-The orchestrator persists them via `conversationStore.append`. If the callback
-isn't called (e.g., test fakes), the orchestrator falls back to batch persist
-after `runTurn` returns — backward compatible.
-
----
-
-## Full endpoint list (current as of [email protected] / [email protected])
-
-### HTTP (port 24203)
-
-| Method | Path | Purpose |
-|---|---|---|
-| `POST` | `/chat` | Stream a turn (NDJSON response, `X-Conversation-Id` header) |
-| `POST` | `/chat/warm` | Cache-warm probe |
-| `GET` | `/models` | Model catalog (now includes `modelInfo` with `contextWindow` per model) |
-| `GET` | `/conversations` | List conversations (`?q=` prefix filter, `?status=active,idle` status filter) |
-| `GET` | `/conversations/:id` | Conversation history (`?sinceSeq=`, `?beforeSeq=`, `?limit=` windowing) |
-| `GET` | `/conversations/:id/metrics` | Per-turn metrics (tokens, timing) |
-| `GET` | `/conversations/:id/last` | Blocking last assistant message |
-| `GET` | `/conversations/:id/cwd` | Per-conversation working directory |
-| `PUT` | `/conversations/:id/cwd` | Set working directory |
-| `GET` | `/conversations/:id/reasoning-effort` | Per-conversation reasoning effort |
-| `PUT` | `/conversations/:id/reasoning-effort` | Set reasoning effort |
-| `GET` | `/conversations/:id/lsp` | LSP server status |
-| `GET` | `/conversations/:id/compact-percent` | Auto-compact percent (0=manual, null=default 85%) |
-| `PUT` | `/conversations/:id/compact-percent` | Set auto-compact percent |
-| `GET` | `/conversations/:id/title` | Read conversation title |
-| `PUT` | `/conversations/:id/title` | Set conversation title |
-| `POST` | `/conversations/:id/close` | Close tab (abort turn + mark `closed`) |
-| `POST` | `/conversations/:id/stop` | **NEW** — Stop generation (abort turn, keep conversation `idle`) |
-| `POST` | `/conversations/:id/compact` | **NEW** — Manual compaction (fork history + replace with summary) |
-| `POST` | `/conversations/:id/open` | **NEW** — Signal FE to open/focus tab (broadcasts `conversation.open`) |
-| `POST` | `/conversations/:id/queue` | Enqueue steering message |
-| `GET` | `/health` | Health check |
-| `GET` | `/metrics/throughput` | Per-model throughput samples |
-| `GET` | `/*` | Static frontend serving (SPA fallback, when `DISPATCH_WEB_DIR` is set) |
-
-### WebSocket (port 24205)
-
-**Client → Server:**
-| Type | Purpose |
-|---|---|
-| `chat.send` | Start a turn (stream events back via `chat.delta`) |
-| `chat.subscribe` | Watch a conversation's turns without sending |
-| `chat.unsubscribe` | Stop watching |
-| `chat.queue` | Enqueue steering (fire-and-forget) |
-| Surface ops | `surface.subscribe`, `surface.invoke`, etc. |
-
-**Server → Client (broadcasts):**
-| Type | Purpose |
-|---|---|
-| `chat.delta` | Per-conversation event (turn-start, text-delta, tool-call, usage, done, etc.) |
-| `chat.error` | Turn error |
-| `conversation.open` | **NEW** — CLI `--open` flag → open/focus a tab |
-| `conversation.statusChanged` | **NEW** — Lifecycle status change (`active`/`idle`/`closed`) |
-| `conversation.compacted` | **NEW** — History compacted (includes `newConversationId` = archive ID) |
-| Surface ops | Catalog, surface data, etc. |
-
-### New types the FE should consume
-
-```ts
-// ConversationMeta ([email protected]) — now has status + compactedFrom
-interface ConversationMeta {
-  id: string;
-  createdAt: number;
-  lastActivityAt: number;
-  title: string;
-  status: "active" | "idle" | "closed";
-  compactedFrom?: string;  // archive ID (pre-compaction history)
-}
-
-// WS messages ([email protected])
-interface ConversationCompactedMessage {
-  type: "conversation.compacted";
-  conversationId: string;
-  newConversationId: string;  // archive ID
-  messagesSummarized: number;
-  messagesKept: number;
-}
-
-// HTTP response types
-interface CompactResponse {
-  conversationId: string;
-  newConversationId: string;  // archive ID
-  messagesSummarized: number;
-  messagesKept: number;
-}
-
-interface CompactPercentResponse {
-  conversationId: string;
-  percent: number;  // 0 = manual; null = default 85
-}
-
-interface SetCompactPercentRequest {
-  percent: number;
-}
-```
-
-### FE handoff docs (in the backend repo)
-
-| File | Feature |
-|---|---|
-| `frontend-conversation-lifecycle-handoff.md` | Tab persistence (active/idle/closed) |
-| `frontend-compaction-handoff.md` | Compacting (non-destructive, chained archives) |
-| `frontend-stop-generation-handoff.md` | Stop generation mid-turn |
-| `frontend-conversation-list-handoff.md` | Conversation list + title + open tab |
-| `frontend-conversation-open-handoff.md` | CLI `--open` → `conversation.open` WS message |
-| `frontend-cache-rate-handoff.md` | Cache hit/miss calculation (updated for providers that don't report cache) |