fix: hide unused wp_note CPT from admin UI to stop "Add New Note" misroute

The plugin registered a wp_note CPT with show_ui=true and show_in_menu=
'wp-notes', which caused WordPress to auto-inject "All Notes" and
"Add New" submenus under the WP Notes admin menu. The "Add New"
submenu routed to post-new.php?post_type=wp_note — the standard WP
post editor — but the live plugin stores notes in wp_options
(get_option('wp_notes')), not as CPT posts. Anyone clicking that
submenu ended up writing to the wrong storage and their note never
appeared in the WP Notes list.

Fix: show_ui and show_in_menu set to false on the wp_note CPT, and
show_ui / show_admin_column / show_in_rest set to false on the
wp_note_category taxonomy. The CPT/taxonomy remain registered so the
wp_notes_migrate_to_cpt() helper can still call wp_insert_post() —
just no admin UI side-effects until the migration is completed and
the live storage swaps over.

Also adds CHANGELOG.md in Keep-a-Changelog format with the
[Unreleased] entry for this fix and a 3.0.2 baseline note for the
"trimmed from v1.1.5 feature-creep" lineage.

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

CHANGELOG.md

@@ -0,0 +1,66 @@
+# Changelog
+
+All notable changes to **A-WP-Notes** are documented here.
+Format: [Keep a Changelog 1.1.0](https://keepachangelog.com/en/1.1.0/) — versioning: [SemVer](https://semver.org/).
+
+---
+
+## [Unreleased]
+
+### Fixed
+- **"Add New Note" sidebar submenu opening the WordPress post editor.**
+  The plugin registered a `wp_note` custom post type with
+  `show_ui => true` and `show_in_menu => 'wp-notes'`, which caused
+  WordPress to auto-inject "All Notes" and "Add New" submenus under
+  the WP Notes admin menu. The "Add New" submenu routed to
+  `post-new.php?post_type=wp_note` — the standard WordPress post
+  editor — but the live plugin stores notes in `wp_options`
+  (`get_option('wp_notes')`), not as CPT posts. Saving in the post
+  editor wrote to the wrong storage and the new note never appeared
+  in the WP Notes list. Discovered 2026-05-25.
+
+  Fixed by setting `show_ui` and `show_in_menu` to `false` on the
+  `wp_note` CPT, and `show_ui` / `show_admin_column` /
+  `show_in_rest` to `false` on the `wp_note_category` taxonomy. The
+  CPT and taxonomy remain registered so `wp_notes_migrate_to_cpt()`
+  can still use `wp_insert_post()` if/when the migration is run.
+  The form on the actual WP Notes page (the one that POSTs to the
+  same admin page) continues to work unchanged.
+
+### Notes
+- The plugin currently uses **two storage models**: the active one is
+  `wp_options` (key `wp_notes`, with completed notes in
+  `wp_done_notes`). The CPT + meta storage is the *target* of an
+  unfinished migration; the helper `wp_notes_migrate_to_cpt()` is
+  defined but unused by the live UI. Until that migration is
+  completed, hiding the CPT from the admin UI prevents users from
+  accidentally writing to the wrong store.
+
+---
+
+## [3.0.2] — 2025-05-10 (last released version, baseline)
+
+The v3 "without all the crap" release. Trimmed from the v1.1.5
+feature-creep era which had bolted on:
+
+- AI chat (multiple variants)
+- AI personalities
+- Journal mode
+- Speedtest
+- Tamagotchi (yes, really)
+- Backup
+- And more
+
+v3 strips back to the essentials:
+
+- Notes list (in `wp_options`)
+- Create note form (color, size, font, emoji)
+- Admin bar quick-access menu
+- Settings page
+- Import / Export
+- About page
+- Update checker
+
+This baseline entry exists for historical context; future releases
+should keep adding entries above and remove this note once a real
+changelog history accrues.