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- tasks.md, HANDOFF.md — outdated status docs (git log is the source of truth)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, 54 deletions

diff --git a/frontend-cr3-user-message-handoff.md b/frontend-cr3-user-message-handoff.md
deleted file mode 100644
index 0fb20e5..0000000
--- a/frontend-cr3-user-message-handoff.md
+++ /dev/null
@@ -1,54 +0,0 @@
-# FE handoff — CR-3 fixed: user prompt is now on the turn's event stream
-
-Courier to `../frontend`. This resolves CR-3 from `backend-handoff.md` ("a watcher can't see
-the turn's USER prompt until seal"). **Option B implemented + live-verified.** Your staged-but-inert
-consumption can now be turned on.
-
-## What shipped (backend)
-
-A new **additive** `AgentEvent` variant carries the user prompt INTO the turn's outward stream:
-
-```ts
-// @dispatch/wire — added to the AgentEvent union
-interface TurnInputEvent {
-  type: "user-message";
-  conversationId: string;
-  turnId: string;
-  text: string;          // the raw prompt, exactly as sent
-}
-```
-
-`session-orchestrator` emits it via the broadcast/buffer path as the **FIRST event of every turn**
-(before `turn-start`), so it is replayed to every subscriber — live AND late-join — and arrives on
-the HTTP/NDJSON path too. Persistence is unchanged (the user message is still appended atomically at
-seal); this only adds a buffered/broadcast event. Metrics are unaffected (it is not usage).
-
-## Version bumps (re-pin both)
-
-- `@dispatch/wire` **`0.5.0 → 0.6.0`** (additive union member).
-- `@dispatch/transport-contract` **`0.7.0 → 0.8.0`** (re-exports `AgentEvent`/`chat.delta`, which now
-  carries `user-message`; no other transport-contract change).
-
-Re-mirror `.dispatch/{wire,transport-contract}.reference.md` and add `user-message` to the FE
-exhaustiveness guard.
-
-## FE action
-
-Flip on the already-staged `core/chunks` branch that folds a `user-message` event into a provisional
-user chunk for watchers, with your text dedup against the sender's optimistic echo. After re-pin:
-- a **pure watcher** (second device / `chat.subscribe` only) now shows the user bubble the moment the
-  turn starts, not at seal;
-- the **sender** is unchanged (its optimistic echo dedups against the replayed `user-message`);
-- a **late-joiner** gets `user-message` first in the replay, then the rest of the in-flight turn.
-
-## Live-verified (backend, vs flash)
-
-Two WS clients on one conversation; client B subscribed but never sent. On A's `chat.send`, B received
-`chat.delta { event:{ type:"user-message", text:"…", turnId, conversationId } }` as its **first** delta
-(index 0), **before** `turn-sealed`, with `text` equal to A's prompt, then the streaming reply. `RESULT: OK`.
-
-## Note
-
-The ordering guarantee is: `user-message` is the first event of the turn, immediately followed by
-`turn-start`, then the usual deltas → `done` → `turn-sealed`. Treat `user-message` as turn-scoped
-(it carries `turnId`) so a multi-turn transcript attributes each prompt to its turn.