Reorganize codebase: separate server architecture from business logic

- Created feed_parser.py module with YouTubeFeedParser and FeedEntry classes
- Refactored main.py to focus on Flask routing with two endpoints:
  - GET / for homepage
  - GET /api/feed for REST API with query parameters
- Updated CLAUDE.md with new architecture documentation
- Implemented clean separation between core logic and web server layers

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

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

.gitignore

@@ -0,0 +1,10 @@
+# Python-generated files
+__pycache__/
+*.py[oc]
+build/
+dist/
+wheels/
+*.egg-info
+
+# Virtual environments
+.venv