CI/CD Optimization: Guard Rails, Pre-commit Checks, and Test Fixes (#90)

* CI/CD Optimization: Guard Rails, Black Linting, and Pre-commit Hooks

- Fixed all test collection errors (Selenium imports, fixture paths, syntax)
- Implemented pre-commit hooks with Black formatting and isort
- Created comprehensive Makefile with test targets (unit, integration, functional, e2e)
- Added pytest.ini with marker definitions for test categorization
- Established guard rails to prevent future collection errors
- Wrapped optional dependencies (Selenium, MoviePy) in try-except blocks
- Added conftest_markers for automatic test categorization

This ensures a smooth development stream with:
- Fast feedback loops (pre-commit checks before push)
- Consistent code formatting (Black)
- Reliable CI/CD (no collection errors, proper test isolation)
- Clear test organization (unit, integration, functional, E2E)

* Fix CI/CD test failures:
- Export templates from dashboard.app
- Fix model name assertion in test_agent.py
- Fix platform-agnostic path resolution in test_path_resolution.py
- Skip Docker tests in test_docker_deployment.py if docker not available
- Fix test_model_fallback_chain logic in test_ollama_integration.py

* Add preventative pre-commit checks and Docker test skipif decorators:
- Create pre_commit_checks.py script for common CI failures
- Add skipif decorators to Docker tests
- Improve test robustness for CI environments

tests/creative/test_assembler_integration.py

@@ -16,7 +16,7 @@ from creative.assembler import (
     add_subtitles,
     export_final,
 )
-from fixtures.media import (
+from tests.fixtures.media import (
     make_audio_track,
     make_video_clip,
     make_scene_clips,