Fix navbar alignment and font size toggle functionality

Fixed two UI issues in the navigation header:

1. **Navbar Alignment**: Added CSS to remove margin/padding from forms in the
   header to ensure the Tutorials button (created with button_to) aligns
   properly with other navbar items like font size controls and user dropdown.

2. **Font Size Toggle**: Added data-turbolinks="false" to font size control
   links to force full page reload. Previously, clicking the small font button
   wouldn't apply changes until manual refresh due to Turbolinks caching. Now
   both font size buttons work immediately.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

app/views/layouts/application.html.erb

@@ -110,6 +110,13 @@
       margin-right: 0;
     }
 
+    /* Fix alignment of button_to forms in header */
+    .rg-header form {
+      margin: 0;
+      padding: 0;
+      display: inline-block;
+    }
+
     /* Modern Sidebar */
     .rg-sidebar {
       position: fixed;