feat: add room-planner app — 3-day HK room view with NewBook integration

NewBook-connected daily housekeeping planner. Replaces the hotelhubmodule-housekeeping-dailylist
WordPress plugin. LXC 120 · 10.10.10.120:3080 · slug: room-planner.

- 3-day booking window (yesterday/today/tomorrow) fetched live from NewBook
- Task completion ticks back to NewBook; room status patches NewBook directly
- 23px border sliver CSS system for adjacent-day booking status
- 3-state filter cycling (off→inclusive→exclusive) for categories and flow types
- Stat filters for outstanding tasks and clean/dirty status
- Rolling 48h activity log with checkout/checkin/status/tasks events
- newbook_pings event bus for future NewBook poller integration
- Room modal with permission-gated guest/rate/notes, task checkboxes, status buttons
- Placeholder sections for future linen-count and routine-tasks modules
- Settings page: task type colours, twin/extra-bed detection, category exclusions
- Mobile-first layout (sidebar desktop, compact top bar mobile)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/nginx.conf

@@ -0,0 +1,23 @@
+server {
+    listen 80;
+
+    location /room-planner/ {
+        alias /usr/share/nginx/html/;
+        try_files $uri $uri/ /room-planner/index.html;
+    }
+
+    location /room-planner/api/ {
+        proxy_pass http://backend:3001/api/;
+        proxy_set_header Host $host;
+        proxy_set_header X-Real-IP $remote_addr;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+        # SSE support
+        proxy_buffering off;
+        proxy_cache off;
+        proxy_read_timeout 3600s;
+    }
+
+    location /room-planner/health {
+        proxy_pass http://backend:3001/health;
+    }
+}