Phase 5.1-5.4: PWA, Public Plugin Endpoints, Contacts Embedding, Search Coverage

5.1 Public Plugin Endpoints:
- PluginRouteDef.is_public field in manifest.py
- main.py: public routes mounted without auth dependency
- permissions/public_routes.py: token-based share link access (info, verify, download)
- permissions/plugin.py: public share route registered with is_public=True

5.2 PWA:
- vite.config.ts: VitePWA plugin configured (autoUpdate, workbox, runtime caching)
- frontend/public/manifest.json: PWA manifest with icons
- index.html: theme-color, manifest link, apple-touch-icon, apple-mobile-web-app meta
- Build generates sw.js + workbox (90 precache entries)

5.3 Contacts Embedding:
- contact.py: embedding column (Vector(768)) added to Contact model
- Migration 0002_embeddings.sql already exists (adds embedding + HNSW index)
- ContactSearchProvider already queries embedding column

5.4 Search Coverage:
- 5 new search providers: task, contactperson, tag, conversation, user
- All providers implement FTS search with tenant_id + deleted_at filters
- TagSearchProvider also supports vector search (384-dim embedding)
- provider_registry.py: all 5 new providers auto-registered
- Total: 10 search providers (was 5)

app/models/contact.py

@@ -172,6 +172,12 @@ class Contact(Base, TenantMixin, OwnedMixin):
         nullable=True,
     )
 
+    # ── Embedding (pgvector, 768-dim) ──
+    from pgvector.sqlalchemy import Vector
+    embedding: Mapped[Any | None] = mapped_column(
+        Vector(768), nullable=True, default=None
+    )
+
     # ── Audit ──
     created_by: Mapped[uuid.UUID | None] = mapped_column(
         PGUUID(as_uuid=True), ForeignKey("users.id", ondelete="SET NULL"), nullable=True