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>

backend/src/db.js

@@ -0,0 +1,70 @@
+import pg from 'pg'
+
+const { Pool } = pg
+export const pool = new Pool({ connectionString: process.env.DATABASE_URL })
+
+export async function initDb() {
+  await pool.query(`
+    -- Instance-level config: task display, twin detection, note visibility, etc.
+    CREATE TABLE IF NOT EXISTS config (
+      key        TEXT PRIMARY KEY,
+      value      JSONB NOT NULL,
+      updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+    );
+
+    -- Rolling activity log. Pruned to 48h on each write.
+    CREATE TABLE IF NOT EXISTS activity_log (
+      id           SERIAL PRIMARY KEY,
+      room_id      TEXT NOT NULL,
+      event_type   TEXT NOT NULL,
+      event_data   JSONB,
+      user_name    TEXT,
+      occurred_at  TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+      service_date DATE NOT NULL,
+      booking_ref  TEXT
+    );
+
+    CREATE INDEX IF NOT EXISTS activity_log_date_idx ON activity_log (service_date, occurred_at DESC);
+
+    -- Lightweight NewBook change signals from the poller. No booking data stored.
+    CREATE TABLE IF NOT EXISTS newbook_pings (
+      id           SERIAL PRIMARY KEY,
+      booking_ids  TEXT[] NOT NULL,
+      event_types  TEXT[] NOT NULL,
+      detected_at  TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+      expires_at   TIMESTAMPTZ NOT NULL DEFAULT NOW() + INTERVAL '5 minutes'
+    );
+
+    CREATE INDEX IF NOT EXISTS newbook_pings_expires_idx ON newbook_pings (expires_at);
+  `)
+
+  await seedDefaultConfig()
+}
+
+async function seedDefaultConfig() {
+  const defaults = {
+    task_display: {},
+    twin_detection: {
+      enabled: true,
+      custom_field_ids: [],
+      keywords: ['twin', 'two single', '2 single', 'single beds', 'sofabed', 'sofa bed'],
+      exclude_keywords: ['twin room', 'twin suite'],
+    },
+    extra_bed_detection: {
+      enabled: true,
+      keywords: ['extra bed', 'extra cot', 'rollaway', 'roll away', 'fold out'],
+    },
+    excluded_categories: [],
+    hide_excluded_categories: false,
+    visible_note_types: [],
+    checkout_notification_timeout: 30,
+    default_checkout_time: process.env.DEFAULT_CHECKOUT_TIME || '11:00',
+  }
+
+  for (const [key, value] of Object.entries(defaults)) {
+    await pool.query(
+      `INSERT INTO config (key, value) VALUES ($1, $2) ON CONFLICT (key) DO NOTHING`,
+      [key, JSON.stringify(value)]
+    )
+  }
+}