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/tests/tasks/test_sync_tasks.py

@@ -12,9 +12,8 @@ Note: These tests mock actual execution since they would require
 external API calls in production.
 """
 
-import pytest
-from unittest.mock import patch
 import uuid
+from unittest.mock import patch
 
 
 class TestSyncIssuesIncrementalTask:
@@ -22,8 +21,8 @@ class TestSyncIssuesIncrementalTask:
 
     def test_sync_issues_incremental_task_exists(self):
         """Test that sync_issues_incremental task is registered."""
-        from app.celery_app import celery_app
         import app.tasks.sync  # noqa: F401
+        from app.celery_app import celery_app
 
         assert "app.tasks.sync.sync_issues_incremental" in celery_app.tasks
 
@@ -56,8 +55,8 @@ class TestSyncIssuesFullTask:
 
     def test_sync_issues_full_task_exists(self):
         """Test that sync_issues_full task is registered."""
-        from app.celery_app import celery_app
         import app.tasks.sync  # noqa: F401
+        from app.celery_app import celery_app
 
         assert "app.tasks.sync.sync_issues_full" in celery_app.tasks
 
@@ -90,8 +89,8 @@ class TestProcessWebhookEventTask:
 
     def test_process_webhook_event_task_exists(self):
         """Test that process_webhook_event task is registered."""
-        from app.celery_app import celery_app
         import app.tasks.sync  # noqa: F401
+        from app.celery_app import celery_app
 
         assert "app.tasks.sync.process_webhook_event" in celery_app.tasks
 
@@ -149,8 +148,8 @@ class TestSyncProjectIssuesTask:
 
     def test_sync_project_issues_task_exists(self):
         """Test that sync_project_issues task is registered."""
-        from app.celery_app import celery_app
         import app.tasks.sync  # noqa: F401
+        from app.celery_app import celery_app
 
         assert "app.tasks.sync.sync_project_issues" in celery_app.tasks
 
@@ -190,8 +189,8 @@ class TestPushIssueToExternalTask:
 
     def test_push_issue_to_external_task_exists(self):
         """Test that push_issue_to_external task is registered."""
-        from app.celery_app import celery_app
         import app.tasks.sync  # noqa: F401
+        from app.celery_app import celery_app
 
         assert "app.tasks.sync.push_issue_to_external" in celery_app.tasks