feat(phase6): docs, lint fixes, STATE.json update

- Fix lint errors in plugin-client.js (unused var, empty block)
- Update README with plugin architecture and env vars
- Update STATE.json to v4.1 IMPLEMENTATION_COMPLETE
- All 96 tests passing, 0 lint errors

README.md

@@ -7,27 +7,47 @@ Agents no longer need to call `live-status`. The watcher auto-updates Mattermost
 
 ## Architecture
 
+Two rendering modes (auto-detected):
+
+### Plugin Mode (preferred)
+When the Mattermost plugin is installed, updates stream via WebSocket:
+- Custom post type `custom_livestatus` with terminal-style React rendering
+- Zero Mattermost post API calls during streaming (no "(edited)" label)
+- Auto-scroll, collapsible sub-agents, theme-compatible
+
+### REST API Fallback
+When the plugin is unavailable, updates use the Mattermost REST API:
+- Blockquote-formatted posts updated via PUT
+- Shows "(edited)" label (Mattermost API limitation)
+
 ```
 OpenClaw Gateway
   Agent Sessions
     -> writes {uuid}.jsonl as they run
 
   status-watcher daemon (SINGLE PROCESS)
-    -> fs.watch recursive on transcript directory (inotify, Node 22)
+    -> fs.watch + polling fallback on transcript directory
     -> Multiplexes all active sessions
-    -> SessionState map: sessionKey -> { postId, pendingToolCalls, lines[] }
+    -> Auto-detects plugin (GET /health every 60s)
+    -> Plugin mode: POST/PUT/DELETE to plugin REST endpoint
+      -> Plugin broadcasts via WebSocket to React component
+    -> REST fallback: PUT to Mattermost post API
     -> Shared HTTP connection pool (keep-alive, maxSockets=4)
-    -> Throttled Mattermost updates (leading edge + trailing flush, 500ms)
+    -> Throttled updates (leading edge + trailing flush, 500ms)
     -> Circuit breaker for API failure resilience
     -> Graceful shutdown (SIGTERM -> mark all boxes "interrupted")
     -> Sub-agent nesting (child sessions under parent status box)
 
+  Mattermost Plugin (com.openclaw.livestatus)
+    -> Go server: REST API + KV store + WebSocket broadcast
+    -> React webapp: custom post type renderer
+    -> Terminal-style UI with auto-scroll
+
   gateway:startup hook
     -> hooks/status-watcher-hook/handler.js
     -> Checks PID file; spawns daemon if not running
-    -> Daemon starts automatically with gateway
 
-  Mattermost API
+  Mattermost API (fallback)
     -> PUT /api/v4/posts/{id} (in-place edits, unlimited)
     -> Shared http.Agent (keepAlive, maxSockets=4)
     -> Circuit breaker: open after 5 failures, 30s cooldown
@@ -89,6 +109,9 @@ All config via environment variables. No hardcoded values.
 | `CIRCUIT_BREAKER_COOLDOWN_S` | `30`                      | Cooldown before half-open probe            |
 | `TOOL_LABELS_FILE`           | _(built-in)_              | External tool labels JSON override         |
 | `DEFAULT_CHANNEL`            | _none_                    | Fallback channel for non-MM sessions       |
+| `PLUGIN_URL`                 | _none_                    | Plugin endpoint URL (enables plugin mode)  |
+| `PLUGIN_SECRET`              | _none_                    | Shared secret for plugin authentication    |
+| `PLUGIN_ENABLED`             | `true`                    | Enable/disable plugin auto-detection       |
 
 ## Status Box Format