Merge branch 'main' into auth

Brought in latest changes from main including:
- RSS feed implementation
- First letter edge case fixes
- Updated ranking formula

Resolved conflicts by:
- Combining .env.example variables from both branches
- Keeping auth version (3.0.0alpha)
- Preserving extended user schema from auth
- Keeping onMount umami approach and adding RSS feed link

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

src/routes/+layout.svelte

@@ -21,11 +21,6 @@
 
 <svelte:head>
   <link rel="icon" href={favicon} />
-  <!-- <script
-    defer
-    src="https://umami.snail.city/script.js"
-    data-website-id="5b8c31ad-71cd-4317-940b-6bccea732acc"
-    data-domains="bibdle.com,www.bibdle.com"
-  ></script> -->
+  <link rel="alternate" type="application/rss+xml" title="Bibdle RSS Feed" href="/feed.xml" />
 </svelte:head>
 {@render children()}