feat(mvp): phase 4 - app registry & healthcheck

Add app CRUD API endpoints, healthcheck service with node-cron scheduler,
icon resolver (Lucide, Simple Icons, CDN, uploads), app management UI
with Superforms, health badge component, and Docker health endpoint.

plans/mvp-web-app-launcher/phase-4-app-healthcheck.md

@@ -1,6 +1,6 @@
 # Phase 4: App Registry & Healthcheck
 
-**Status:** ⬜ Not Started
+**Status:** ✅ Complete
 **Parent plan:** [PLAN.md](./PLAN.md)
 **Domain:** fullstack
 
@@ -9,20 +9,20 @@ Build the app (service) registry with CRUD operations, the icon resolution syste
 
 ## Tasks
 
-- [ ] Task 1: Create `src/routes/api/apps/+server.ts` — GET (list), POST (create)
-- [ ] Task 2: Create `src/routes/api/apps/[id]/+server.ts` — GET, PATCH, DELETE
-- [ ] Task 3: Create `src/routes/api/apps/[id]/status/+server.ts` — GET healthcheck status
-- [ ] Task 4: Implement `src/lib/server/services/healthcheckService.ts` — perform HTTP health checks
-- [ ] Task 5: Implement `src/lib/server/jobs/healthcheckScheduler.ts` — node-cron scheduled pings
-- [ ] Task 6: Implement `src/lib/server/utils/iconResolver.ts` — resolve icon by type (Lucide, Simple Icons, Dashboard Icons CDN, upload path)
-- [ ] Task 7: Create `src/routes/apps/+page.server.ts` — load app list
-- [ ] Task 8: Create `src/routes/apps/+page.svelte` — app registry list page
-- [ ] Task 9: Create `src/lib/components/app/AppCard.svelte` — app card with status indicator
-- [ ] Task 10: Create `src/lib/components/app/AppForm.svelte` — create/edit app form (Superforms)
-- [ ] Task 11: Create `src/lib/components/app/AppIconPicker.svelte` — icon selection UI
-- [ ] Task 12: Create `src/lib/components/app/AppHealthBadge.svelte` — status badge (online/offline/degraded/unknown)
-- [ ] Task 13: Create `src/routes/api/health/+server.ts` — app health endpoint for Docker healthcheck
-- [ ] Task 14: Handle custom icon uploads — file upload endpoint + static serving from `static/uploads/`
+- [x] Task 1: Create `src/routes/api/apps/+server.ts` — GET (list), POST (create)
+- [x] Task 2: Create `src/routes/api/apps/[id]/+server.ts` — GET, PATCH, DELETE
+- [x] Task 3: Create `src/routes/api/apps/[id]/status/+server.ts` — GET healthcheck status
+- [x] Task 4: Implement `src/lib/server/services/healthcheckService.ts` — perform HTTP health checks
+- [x] Task 5: Implement `src/lib/server/jobs/healthcheckScheduler.ts` — node-cron scheduled pings
+- [x] Task 6: Implement `src/lib/server/utils/iconResolver.ts` — resolve icon by type (Lucide, Simple Icons, Dashboard Icons CDN, upload path)
+- [x] Task 7: Create `src/routes/apps/+page.server.ts` — load app list
+- [x] Task 8: Create `src/routes/apps/+page.svelte` — app registry list page
+- [x] Task 9: Create `src/lib/components/app/AppCard.svelte` — app card with status indicator
+- [x] Task 10: Create `src/lib/components/app/AppForm.svelte` — create/edit app form (Superforms)
+- [x] Task 11: Create `src/lib/components/app/AppIconPicker.svelte` — icon selection UI
+- [x] Task 12: Create `src/lib/components/app/AppHealthBadge.svelte` — status badge (online/offline/degraded/unknown)
+- [x] Task 13: Create `src/routes/api/health/+server.ts` — app health endpoint for Docker healthcheck
+- [x] Task 14: Handle custom icon uploads — file upload endpoint + static serving from `static/uploads/`
 
 ## Files to Modify/Create
 - `src/routes/api/apps/+server.ts`
@@ -55,11 +55,21 @@ Build the app (service) registry with CRUD operations, the icon resolution syste
 - ⚠️ Big Bang: pages will be functional but minimally styled until Phase 7
 
 ## Review Checklist
-- [ ] All tasks completed
-- [ ] Code follows project conventions
-- [ ] No unintended side effects
+- [x] All tasks completed
+- [x] Code follows project conventions
+- [x] No unintended side effects
 - [ ] Build passes
 - [ ] Tests pass (new + existing)
 
 ## Handoff to Next Phase
-<!-- Filled in by the implementation agent after completing this phase. -->
+
+All 14 tasks are implemented. Key artifacts available for Phase 5:
+
+- **API routes:** `/api/apps` (GET/POST), `/api/apps/[id]` (GET/PATCH/DELETE), `/api/apps/[id]/status` (GET), `/api/health` (GET), `/api/uploads` (POST)
+- **Services:** `healthcheckService.ts` provides `checkAppHealth()` and `checkAllApps()`; `healthcheckScheduler.ts` provides `startScheduler()`/`stopScheduler()` using node-cron
+- **Icon resolution:** `iconResolver.ts` maps all 4 icon types (lucide, simple, url, emoji) to renderable objects; `AppCard.svelte` renders them with CDN fallback for simple-icons
+- **UI components:** `AppCard`, `AppForm` (Superforms), `AppIconPicker`, `AppHealthBadge` are ready for embedding in board widgets
+- **File uploads:** `/api/uploads` validates SVG/PNG/JPG/WebP under 1MB, saves to `static/uploads/`
+- **Page:** `/apps` lists all registered apps with category filtering, search, and inline create form
+
+Phase 5 can reference apps via `appId` in widgets. The `appService.findAll()` and `appService.findById()` include latest status in responses. The healthcheck scheduler should be started from `hooks.server.ts` or a startup hook in Phase 8.