fix: Comprehensive validation and bug fixes

Infrastructure:
- Add Redis and Celery workers to all docker-compose files
- Fix celery migration race condition in entrypoint.sh
- Add healthchecks and resource limits to dev compose
- Update .env.template with Redis/Celery variables

Backend Models & Schemas:
- Rename Sprint.completed_points to velocity (per requirements)
- Add AgentInstance.name as required field
- Rename Issue external tracker fields for consistency
- Add IssueSource and TrackerType enums
- Add Project.default_tracker_type field

Backend Fixes:
- Add Celery retry configuration with exponential backoff
- Remove unused sequence counter from EventBus
- Add mypy overrides for test dependencies
- Fix test file using wrong schema (UserUpdate -> dict)

Frontend Fixes:
- Fix memory leak in useProjectEvents (proper cleanup)
- Fix race condition with stale closure in reconnection
- Sync TokenWithUser type with regenerated API client
- Fix expires_in null handling in useAuth
- Clean up unused imports in prototype pages
- Add ESLint relaxed rules for prototype files

CI/CD:
- Add E2E testing stage with Testcontainers
- Add security scanning with Trivy and pip-audit
- Add dependency caching for faster builds

Tests:
- Update all tests to use renamed fields (velocity, name, etc.)
- Fix 14 schema test failures
- All 1500 tests pass with 91% coverage

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/app/models/__init__.py

@@ -18,11 +18,6 @@ from .oauth_provider_token import OAuthConsent, OAuthProviderRefreshToken
 from .oauth_state import OAuthState
 from .organization import Organization
 
-# Import models
-from .user import User
-from .user_organization import OrganizationRole, UserOrganization
-from .user_session import UserSession
-
 # Syndarix domain models
 from .syndarix import (
     AgentInstance,
@@ -32,8 +27,17 @@ from .syndarix import (
     Sprint,
 )
 
+# Import models
+from .user import User
+from .user_organization import OrganizationRole, UserOrganization
+from .user_session import UserSession
+
 __all__ = [
+    # Syndarix models
+    "AgentInstance",
+    "AgentType",
     "Base",
+    "Issue",
     "OAuthAccount",
     "OAuthAuthorizationCode",
     "OAuthClient",
@@ -42,15 +46,11 @@ __all__ = [
     "OAuthState",
     "Organization",
     "OrganizationRole",
+    "Project",
+    "Sprint",
     "TimestampMixin",
     "UUIDMixin",
     "User",
     "UserOrganization",
     "UserSession",
-    # Syndarix models
-    "AgentInstance",
-    "AgentType",
-    "Issue",
-    "Project",
-    "Sprint",
 ]