docs: rewrite README to match current architecture

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

README.md

@@ -1,22 +1,65 @@
 # Fabric.Backend.Guild
 
-Guild Node service for Fabric.
+A **guild node** for Fabric (NestJS, ES modules, MySQL/TypeORM,
+socket.io). Default port `7002`, global prefix `/api`. Many independent
+guild nodes can run; each registers with `Fabric.Backend.Center` and
+introspects the user/guild tokens Center issues.
 
-## Scope (MVP)
-- Workspace/Guild/Channel/DM
-- Message create/edit/delete/reply/@mention
-- Per-channel/DM seq ordering + gap backfill API
-- Webhook/Bot integration surface
-- Guild-level audit logs
+## Responsibilities
 
-## Next
-- API skeleton (NestJS)
-- Chat domain models
-- Seq allocator and range query endpoints
+- **Guilds / channels / messaging** — per-channel `seq` ordering, edit
+  window, soft delete, reply, `<@id>` mentions (backtick-aware) plus
+  `<@user.name:NAME>` → `<@userId>` translation via Center.
+- **Channel `x_type`** (required on create): `general`, `work`, `report`,
+  `discuss`, `triage`, `custom`. Plus `isPublic` and `closed` (closed →
+  history readable, posting returns `409`).
+- **`wake_mapping`** — explicit wake list for `triage` (on-duty) and
+  `custom` (listeners) channels.
+- **Per-recipient `wakeup`** — `message.created` is emitted per socket with
+  its own `wakeup` flag (author=false; general→all; report→none;
+  triage/custom→wake_mapping; discuss/work→the current speaker only). This
+  is **push-only metadata for the OpenClaw plugin**; UIs ignore it.
+- **discuss/work turn engine** (`channel_turn_state`): speaking order and a
+  disjoint **bypass list** (bypass members aren't woken unless @-mentioned);
+  activation from idle, queue-jump, cross-round `/no-reply` pause,
+  `/force-proceed`, end-of-round shuffle, guild `/ack`, and a mention
+  sub-frame stack with a 5-level nesting cap (root + 4). `moveToBypass`
+  mid-rotation.
+- **Files** — `POST /files` (multipart, configurable max size, default
+  100 MB), `GET /files/:id` (Bearer **or** `?access_token=` for browser
+  `<img>/<a>`), automatic retention sweep (default 7 days). Messages carry
+  `attachments[]`.
+- **Channel canvas** — one pinned document per channel (`md`/`html`/`text`),
+  re-share replaces, only the original sharer may update/remove; emits
+  `canvas.updated` / `canvas.removed`.
+- **Realtime** — socket.io `/realtime`; `join_channel`/`leave_channel`,
+  `message.created/updated/deleted`, `canvas.*`, presence, typing.
+
+## Required env (hard-checked at startup)
 
-## Required env (startup hard checks)
 - `FABRIC_BACKEND_GUILD_CENTER_BASE_URL`
 - `FABRIC_BACKEND_GUILD_CENTER_API_KEY`
 - `FABRIC_BACKEND_GUILD_NODE_ID`
 
-If any of the above is missing, service startup fails immediately.
+Missing any of these aborts startup.
+
+## Other env
+
+- `FABRIC_BACKEND_GUILD_PORT` (default 7002)
+- `FABRIC_BACKEND_GUILD_DB_*`, `FABRIC_BACKEND_GUILD_DB_SYNC`
+- `FABRIC_BACKEND_GUILD_FILE_DIR` (storage root),
+  `FABRIC_BACKEND_GUILD_FILE_MAX_BYTES` (default 100 MB),
+  `FABRIC_BACKEND_GUILD_FILE_TTL_DAYS` (default 7)
+- `FABRIC_BACKEND_GUILD_CORS_ORIGINS` (empty = allow all; `null` origin —
+  `file://` desktop — is always allowed)
+
+## Run
+
+```bash
+npm install
+npm run build && npm start          # or: npm run start:dev
+```
+
+Usually run via the root `docker-compose.local.yml` (`backend-guild1`
+`test-guild1` :7002, `backend-guild2` `test-guild2` :7003). Schema is
+auto-managed (`DB_SYNC`). ES modules (`NodeNext`).