feat(01-04): FastAPI portal API endpoints with tenant/agent CRUD and auth

- Add packages/shared/shared/api/portal.py with APIRouter at /api/portal
- POST /auth/verify validates bcrypt credentials against portal_users table
- POST /auth/register creates new portal users with hashed passwords
- Tenant CRUD: GET/POST /tenants, GET/PUT/DELETE /tenants/{id}
- Agent CRUD: full CRUD under /tenants/{tenant_id}/agents/{id}
- Agent endpoints set RLS current_tenant_id context for policy compliance
- Pydantic v2 schemas with slug validation (lowercase, hyphens, 2-50 chars)
- Add bcrypt>=4.0.0 dependency to konstruct-shared
- Integration tests: 38 tests covering all CRUD, validation, and isolation

packages/shared/pyproject.toml

@@ -18,6 +18,7 @@ dependencies = [
     "celery[redis]>=5.4.0",
     "httpx>=0.28.0",
     "slowapi>=0.1.9",
+    "bcrypt>=4.0.0",
 ]
 
 [tool.hatch.build.targets.wheel]