ux: rename "Create WP Note" → "My Notes" and "About WP Notes" → "About"

The "Create WP Note" submenu was misleadingly narrow — that page is
the central dashboard (create form + active list + completed list +
edit + restore). Renamed to "My Notes" to match the WP-native
"Posts → All Posts" pattern and reflect that users land there for
everything, not just creation.

"About WP Notes" → "About": the WP Notes brand is already carried by
the parent menu, so the submenu can be plain-spoken.

CHANGES
- wp-notes.php: WP Notes submenu "Create WP Note" → "My Notes"
- wp-notes.php: Tools menu shortcut "Create WP Note" → "My Notes"
  (same target page)
- wp-notes.php: WP Notes submenu "About WP Notes" → "About"
- wp-notes.php: callback docblock updated to reflect new name
- inc/wp-notes-about.php: page H1 trimmed to match the Tier-1 style
  on the main page (h1 "About" + version chip + wp-header-end hr),
  replacing the previous "Welcome to WP Notes About Page v3.0.2"
- inc/wp-notes-about.php: removed a redundant nested
  <div id="header"> with display:none that was dead markup leftover
  from an older layout

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

inc/wp-notes-about.php

@@ -39,6 +39,12 @@ function wp_notes_about_page() {
         }
     </style>
 
+    <div class="wrap">
+        <h1 class="wp-heading-inline">About</h1>
+        <span class="page-title-action">v<?php echo esc_html(WP_NOTES_VERSION); ?></span>
+        <hr class="wp-header-end">
+    </div>
+
     <div class="wrap" style="display: flex; gap: 20px;">
         <!-- Left Section: About Content (70%) -->
         <div style="flex: 0 0 70%;">
@@ -58,14 +64,11 @@ function wp_notes_about_page() {
                 </div>
             </div>
 
-            <h1>Welcome to WP Notes About Page v <?php echo esc_html(WP_NOTES_VERSION); ?></h1>
-            <div class="wp-notes-welcome" style="background: #fff; padding: 20px; margin: 20px 0; border: 1px solid #ccc;">
-            <p>WP Notes is your task management solution for WordPress. Keep track of your todos, collaborate with team members, and never lose important notes.</p>
-            <div id="header" style="display: none; margin-top: 10px;">
-            </div>
-            </div>
             <style>
-            /* Hides most plugin notices */
+            /* Hide most plugin notices on the About page — they push the
+               long-form content down and the user came here to read, not
+               to dismiss admin chatter. Scoped to the About page only by
+               virtue of living in this file. */
             .notice, .updated, .error {
                 display: none !important;
             }