fix: persistent daemon startup, plugin integration, mobile fallback

- Hook handler now loads .env.daemon for proper config (plugin URL/secret, bot user ID)
- Hook logs to /tmp/status-watcher.log instead of /dev/null
- Added .env.daemon config file (.gitignored - contains tokens)
- Added start-daemon.sh convenience script
- Plugin mode: mobile fallback updates post message field with formatted markdown
- Fixed unbounded lines array in status-watcher (capped at 50)
- Added session marker to formatter output for restart recovery
- Go plugin: added updatePostMessageForMobile() for dual-render strategy
  (webapp gets custom React component, mobile gets markdown in message field)

Fixes: daemon silently dying, no plugin connection, mobile showing blank posts

src/status-formatter.js

@@ -76,6 +76,8 @@ function format(sessionState, opts = {}) {
         return '> ' + l;
       })
       .join('\n');
+    // Append invisible session marker for restart recovery (search by marker)
+    body += '\n<!-- sw:' + sessionState.sessionKey + ' -->';
   }
   return body;
 }