chore: advance jQuery migration by upgrading to 3.7.1 with modern Migrate

Move to the latest stable jQuery (3.7.1) and jQuery UI (1.14.1), replacing outdated 1.9.1 versions. This continues our incremental modernization path.

Update jQuery Migrate to 3.4.1 to match, ensuring accurate deprecation warnings during development. The new Migrate version supports the latest APIs and provides better debugging feedback.

All existing behavior is preserved. Warnings in the console should now reflect any remaining legacy patterns that need cleanup.

Part of the migration sequence:
- Previous: refactor .bind()/.click() → .on()
- This: upgrade core libraries
- Next: remove Migrate once clean

Author: RafaelJohn9

layouts/partials/footer.html

@@ -11,9 +11,9 @@
   <img src="{{ relURL "images/icons/chevron-up@2x.png" }}" width="20" height="20" alt="scroll-to-top"/>
 </a>
 
-<script src="https://code.jquery.com/jquery-1.9.1.min.js"></script>
-<script src="https://code.jquery.com/ui/1.9.1/jquery-ui.min.js"></script>
-<script src="https://code.jquery.com/jquery-migrate-1.2.1.js"></script>
+<script src="https://code.jquery.com/jquery-3.7.1.min.js"></script>
+<script src="https://code.jquery.com/ui/1.14.1/jquery-ui.min.js"></script>
+<script src="https://code.jquery.com/jquery-migrate-3.4.1.js"></script>
 <script src="{{ relURL "js/jquery.defaultvalue.js" }}"></script>
 <script src="{{ relURL "js/session.min.js" }}"></script>
 {{ $js := resources.Get "js/application.js" | resources.ExecuteAsTemplate "js/application.js" . | resources.Minify | fingerprint }}