feat: Add hybrid quality evaluation system with CLIP and VLM support

- Add FeatureExtractor for CLIP-based image/text feature extraction
- Add ObjectiveMetricsCalculator for technical quality metrics
- Add VLMEvaluator for vision language model evaluation
- Add HybridQualityGate combining objective + VLM evaluation
- Enhance CharacterMemory with visual feature support
- Add quality optional dependency (torch, ftfy, regex)
- Add unit tests for new modules

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

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

pyproject.toml

@@ -34,6 +34,11 @@ dev = [
     "pytest-asyncio>=0.23.0",
     "ruff>=0.6.0",
 ]
+quality = [
+    "torch>=2.0.0",
+    "ftfy>=6.1.0",
+    "regex>=2023.0.0",
+]
 
 [project.scripts]
 pixelle-video = "pixelle_video.cli:main"