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>

feed_parser.py

@@ -0,0 +1,68 @@
+"""YouTube RSS feed parser module.
+
+This module handles fetching and parsing YouTube channel RSS feeds,
+with filtering capabilities to exclude unwanted content like Shorts.
+"""
+
+import feedparser
+from typing import Dict, List, Optional
+
+
+class FeedEntry:
+    """Represents a single entry in a YouTube RSS feed."""
+
+    def __init__(self, title: str, link: str):
+        self.title = title
+        self.link = link
+
+    def to_dict(self) -> Dict[str, str]:
+        """Convert entry to dictionary."""
+        return {
+            "title": self.title,
+            "link": self.link
+        }
+
+
+class YouTubeFeedParser:
+    """Parser for YouTube channel RSS feeds."""
+
+    BASE_URL = "https://www.youtube.com/feeds/videos.xml"
+
+    def __init__(self, channel_id: str):
+        """Initialize parser with a YouTube channel ID.
+
+        Args:
+            channel_id: The YouTube channel ID to fetch feeds from
+        """
+        self.channel_id = channel_id
+        self.url = f"{self.BASE_URL}?channel_id={channel_id}"
+
+    def fetch_feed(self, filter_shorts: bool = True) -> Optional[Dict]:
+        """Fetch and parse the RSS feed.
+
+        Args:
+            filter_shorts: If True, exclude YouTube Shorts from results
+
+        Returns:
+            Dictionary containing feed metadata and entries, or None if fetch fails
+        """
+        feed = feedparser.parse(self.url)
+
+        if feed.status != 200:
+            return None
+
+        entries = []
+        for entry in feed.entries:
+            if filter_shorts and "shorts" in entry.link:
+                continue
+
+            entries.append(FeedEntry(
+                title=entry.title,
+                link=entry.link
+            ))
+
+        return {
+            "feed_title": feed.feed.title,
+            "feed_link": feed.feed.link,
+            "entries": [entry.to_dict() for entry in entries]
+        }