feat: Add RSS feed generation for blog posts

Introduces a function to generate an RSS feed from blog posts,
ensuring dates are in RFC 822 format. Sorts posts by date and
includes development mode support for URLs. Adds RSS template
to render the feed with metadata and posts from the blog.

Enhances blog visibility and syndication capabilities.

main.py

@@ -188,7 +188,9 @@ def generate_blog_html(posts_per_page=5):
     # Render each individual post
     for post in blog_posts:
         post.setdefault("license", "CC BY-SA 4.0")
-        post.setdefault("license-url", "https://creativecommons.org/licenses/by-sa/4.0/")
+        post.setdefault(
+            "license-url", "https://creativecommons.org/licenses/by-sa/4.0/"
+        )
         post.setdefault("author", "Private.coffee Team")
         post.setdefault("author-url", "https://private.coffee")
 
@@ -202,6 +204,45 @@ def generate_blog_html(posts_per_page=5):
     print("Blog section generated successfully.")
 
 
+def generate_blog_rss(development_mode=False):
+    blog_dir = pathlib.Path("blog")
+    blog_posts = []
+
+    for post_dir in blog_dir.iterdir():
+        if post_dir.is_dir():
+            md_path = post_dir / "index.md"
+            if md_path.exists():
+                front_matter, _ = parse_markdown_file(md_path)
+
+                # Ensure date is RFC 822 compliant
+                if "date" in front_matter:
+                    if isinstance(front_matter["date"], str):
+                        post_date = datetime.datetime.strptime(
+                            front_matter["date"], "%Y-%m-%d %H:%M:%S"
+                        )
+                    else:
+                        post_date = front_matter["date"]
+                    front_matter["date"] = post_date.strftime(
+                        "%a, %d %b %Y %H:%M:%S %z"
+                    )
+
+                front_matter["link"] = (
+                    f"https://{"dev." if development_mode else ""}private.coffee/blog/{post_dir.name}/"
+                )
+
+                blog_posts.append(front_matter)
+
+    blog_posts.sort(key=lambda x: x.get("date", ""), reverse=True)
+
+    context = {
+        "posts": blog_posts,
+        "current_time": datetime.datetime.now().strftime("%a, %d %b %Y %H:%M:%S %z"),
+    }
+    render_template_to_file("blog/rss.xml", "blog/rss.xml", **context)
+
+    print("RSS feed generated successfully.")
+
+
 def generate_static_site(development_mode=False, theme="plain"):
     # Common context
     kwargs = {
@@ -279,6 +320,7 @@ def generate_static_site(development_mode=False, theme="plain"):
 
     # Generate blog section
     generate_blog_html()
+    generate_blog_rss(development_mode)
 
     # Generate metrics
     balances = get_transparency_data(finances, allow_current=True)["end_balance"]