Add tag filtering and fix browser title

- Tag filter bar appears when any prayers have tags; click to filter,
  click again or hit Clear to reset. Tags on cards are also clickable.
- Status filter and tag filter combine (e.g. active + family tag).
- Browser tab title changed from 'React App' to 'Prayer Journal'.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DReRqHxSYuVfCzTzQGD9hZ

public/index.html

@@ -24,7 +24,7 @@
       work correctly both with client-side routing and a non-root public URL.
       Learn how to configure a non-root public URL by running `npm run build`.
     -->
-    <title>React App</title>
+    <title>Prayer Journal</title>
   </head>
   <body>
     <noscript>You need to enable JavaScript to run this app.</noscript>