feat: Sprint 5 — AI insights, webhooks/Slack, PWA, performance monitoring

AI-Powered Insights (G9):
- Rule-based anomaly detection: budget burn rate, staffing gaps, utilization,
  timeline overruns across all active projects
- AI narrative generation via existing Azure OpenAI integration
- Cached in project dynamicFields to avoid regeneration
- New /analytics/insights page with anomaly feed + project summaries
- Sidebar nav: "AI Insights" under Analytics

Webhook System + Slack (G10):
- Webhook model in Prisma (url, secret, events, isActive)
- HMAC-SHA256 signed payloads with 5s timeout fire-and-forget dispatch
- Slack-aware: routes hooks.slack.com URLs through Slack formatter
- 6 events integrated: allocation.created/updated/deleted, project.created/
  status_changed, vacation.approved
- Admin UI: /admin/webhooks with CRUD, test button, event checkboxes
- webhook router: list, getById, create, update, delete, test

PWA Support (G11):
- manifest.json with standalone display, brand-colored icons (192+512px)
- Service worker: cache-first for static, network-first for API, offline fallback
- ServiceWorkerRegistration component with 60-min update checks
- InstallPrompt banner with 30-day dismissal memory
- Apple Web App meta tags + viewport theme color

Performance Monitoring (A15):
- Pino structured logging (JSON prod, pretty dev) via LOG_LEVEL env
- tRPC logging middleware on all protectedProcedure calls
- Request ID (UUID) per call for log correlation
- Slow query warnings (>500ms) at warn level
- GET /api/perf endpoint: memory, uptime, SSE connections, node version

Fix: renamed scenario.apply to scenario.applyScenario (tRPC reserved word)

Co-Authored-By: claude-flow <ruv@ruv.net>

apps/web/public/manifest.json

@@ -0,0 +1,14 @@
+{
+  "name": "Planarchy — Resource Planning",
+  "short_name": "Planarchy",
+  "description": "Resource planning and project staffing for 3D production",
+  "start_url": "/dashboard",
+  "display": "standalone",
+  "background_color": "#ffffff",
+  "theme_color": "#0284c7",
+  "orientation": "any",
+  "icons": [
+    { "src": "/icon-192.png", "sizes": "192x192", "type": "image/png", "purpose": "any maskable" },
+    { "src": "/icon-512.png", "sizes": "512x512", "type": "image/png", "purpose": "any maskable" }
+  ]
+}