refactor: remove Trash system — delete is now permanent with confirm modal

Remove all vestiges of the abandoned Trash system: trashed/trashedAt fields
from types, frontmatter parsing, sidebar filtering, editor banners, inspector
components, mock data, and all related tests. Delete is already permanent via
useDeleteActions with a confirmation dialog. Notes with trashed:true in
existing vault frontmatter are now treated as normal notes (the flag is
ignored by the parser).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/components/note-list/noteListUtils.test.ts

@@ -6,7 +6,7 @@ function makeEntry(path = '/test.md'): VaultEntry {
   return {
     path, filename: 'test.md', title: 'Test', isA: null,
     aliases: [], belongsTo: [], relatedTo: [], status: null,
-    archived: false, trashed: false, trashedAt: null,
+    archived: false,
     modifiedAt: null, createdAt: null, fileSize: 0,
     snippet: '', wordCount: 0, relationships: {},
     icon: null, color: null, order: null, sidebarLabel: null,