NextGraph integration (WIP), broker banner, and feature-based architecture

- Add NextGraph data layer with @ng-org/orm, SHEX shapes (Event, UserProfile,
  Participation), session management, and FestipodDataContext with dual-mode
  operation (connected via NextGraph or local seed data)
- Add BrokerBanner and NgStatus components showing connection status
- Refactor to feature-based architecture: organize code by business domain
  (event, user, home, auth, workshop, meeting, notification) instead of
  technical layer. Modules only import from shared/, never from each other
- Collocate BDD features and step definitions with their modules: event-specific
  steps in event/steps/, user steps in user/steps/, shared generic steps remain
  in shared/steps/
- Set up multi-layer BDD structure (frontend/backend/e2e steps per module)
- Add project documentation (AGENTS.md, .project/knowledge/)

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

AGENTS.md

@@ -0,0 +1,47 @@
+# Festipod
+
+Prototyping tool for a mobile festival/event app — mockup screens, user stories, and BDD specs.
+
+## Two Apps in One
+
+| Layer | Tech | Purpose |
+|-------|------|---------|
+| **Festipod App** (mockups) | React + sketchy components | 16 mobile screens with hand-drawn UI |
+| **Prototyping Tool** (shell) | React + Tailwind/Shadcn | Gallery, demo viewer, BDD specs browser |
+
+## Architecture
+
+Feature-based: code organized by business domain, not technical layer. See [architecture](.project/knowledge/architecture.md).
+
+```
+src/modules/{event,user,home,auth,workshop,meeting,notification}/
+src/shared/          # Components, context, data — importable by all modules
+src/app/             # Prototyping tool shell
+src/screens/index.ts # Screen registry
+```
+
+## Data Layer
+
+NextGraph (P2P/local-first) with SHEX shapes and ORM. See [data-layer](.project/knowledge/data-layer.md).
+
+## BDD Testing
+
+Multi-layer Cucumber/Gherkin in French. See [bdd-testing](.project/knowledge/bdd-testing.md).
+
+## Quick Start
+
+```bash
+bun run dev              # Dev server with HMR (port 3000)
+bun run build            # Production build to dist/
+bun run test:cucumber    # Run all BDD tests
+bun run features:parse   # Regenerate features.ts from .feature files
+bun run steps:extract    # Extract step definitions for tooltips
+bun run build:orm        # Regenerate ORM from SHEX shapes
+```
+
+## Documentation
+
+- [Architecture](.project/knowledge/architecture.md) — module structure, import rules, app shell
+- [Data Layer](.project/knowledge/data-layer.md) — NextGraph, shapes, context, seed data
+- [BDD Testing](.project/knowledge/bdd-testing.md) — Cucumber setup, step layers, feature files
+- [Screens](.project/knowledge/screens.md) — screen inventory, registry, sketchy components