[pending-judge] feat(DC-161): calendar widget + Radicale auto-wiring

- Top-bar calendar widget (status/js/calendar-widget.js): next-appointment
  display, settings modal with CalDAV/ICS source management and a
  Test-connection probe. Follows the weather-widget pattern.
- Backend routes/calendar.js: sources CRUD (secrets in credential manager,
  never in responses), aggregated events across sources with per-source
  error isolation, Radicale provision endpoint, CalDAV discover probe.
- src/calendar/ics-parser.js: dependency-free RFC 5545 parser with bounded
  RRULE expansion (DAILY/WEEKLY-BYDAY/MONTHLY/YEARLY, COUNT/UNTIL/INTERVAL,
  EXDATE consumes COUNT, RECURRENCE-ID overrides), 500-event cap.
- src/calendar/caldav-client.js: CalDAV REPORT time-range queries over
  node:https (no new deps), HTTPS-enforced off localhost, 5MiB response cap.
- src/calendar/radicale-provisioner.js: zero-config auto-wiring - generates
  a 24-char password, writes Radicale htpasswd config (pure-Node APR1 hash
  verified byte-for-byte against openssl passwd -apr1 vectors), stores
  credentials, registers the source. Deploy hook in routes/apps/deploy.js
  wires any Radicale deployed via the App Selector automatically.
- Radicale app template (tomsquest/docker-radicale) in the catalog.
- Tests: 32 new (parser unit, provisioner unit incl. openssl vectors,
  route tests). Full suite 3552 passed; only pre-existing pdf-parse
  billing/invoice failures remain (proven red at base 448f535).
- OpenAPI: 5 calendar paths documented. CHANGELOG entry added.

dashcaddy-api/src/app.js

@@ -94,6 +94,8 @@ const sitesRoutes = require('../routes/sites');
 const credentialsRoutes = require('../routes/credentials');
 const arrRoutes = require('../routes/arr');
 const appsRoutes = require('../routes/apps');
+// DC-161: calendar widget backend (CalDAV/ICS sources + Radicale auto-wiring)
+const calendarRoutes = require('../routes/calendar');
 const logsRoutes = require('../routes/logs');
 const backupsRoutes = require('../routes/backups');
 const caRoutes = require('../routes/ca');
@@ -159,6 +161,10 @@ async function createApp() {
   // Create state managers
   const servicesStateManager = new StateManager(config.SERVICES_FILE);
   const configStateManager = new StateManager(config.CONFIG_FILE);
+  // DC-161: calendar sources live next to services.json (same dataDir guarantees)
+  const calendarStateManager = new StateManager(
+    require('path').join(require('path').dirname(config.SERVICES_FILE), 'calendar-sources.json')
+  );
 
   // DC-053: share-store. Single shared instance, lazy file creation on first
   // write. Lives alongside user-store/invite-store semantics (defensive
@@ -917,6 +923,18 @@ async function createApp() {
   }));
   apiRouter.use(arrRoutes(ctx));
   apiRouter.use(appsRoutes(ctx));
+  // DC-161: calendar — sources CRUD, aggregated events, Radicale auto-provision
+  apiRouter.use('/calendar', calendarRoutes({
+    calendarStateManager,
+    credentialManager: ctx.credentialManager,
+    docker: ctx.docker,
+    asyncHandler: ctx.asyncHandler,
+    ok: ctx.ok,
+    errorResponse: ctx.errorResponse,
+    log: ctx.log,
+    fetchT: ctx.fetchT,
+    buildServiceUrl: ctx.buildServiceUrl,
+  }));
   apiRouter.use('/openclaw', openClawRoutes(ctx));
   apiRouter.use(logsRoutes({
     asyncHandler: ctx.asyncHandler,