fix: stabilize markdown notes — internal link modal, rename UI, trash integration

- Replace broken ObjectPickerModal with simple inline modal (Label+URL fields)
- Insert internal link at cursor position in textarea
- Add rename button in note editor header and note cards
- Add delete button on note cards with confirm dialog
- Integrate DeleteNote with shared trash (.verstak/trash/) via files.TrashFile()
- Remove hidden .verstak/trash/notes/ folder — notes use unified trash now
- Fix purgeTrashNode to clean file-record-based trash entries (notes/files)
- Add activity + sync ops to DeleteNote binding
- Add files.TrashFile() public method
- Update i18n keys for note.rename, note.deleteConfirm, internal link modal
- AssertContained: symlink-aware path containment check
- Update tests: shared trash, file record missing flag, collision on rename
- All go test ./... pass, frontend build passes, GUI binary built

frontend/src/wailsjs/go/main/App.js

@@ -46,6 +46,14 @@ export function SaveNote(arg1, arg2) {
     return window['go']['main']['App']['SaveNote'](arg1, arg2);
 }
 
+export function RenameNote(arg1, arg2) {
+    return window['go']['main']['App']['RenameNote'](arg1, arg2);
+}
+
+export function DeleteNote(arg1) {
+    return window['go']['main']['App']['DeleteNote'](arg1);
+}
+
 export function ListFiles(arg1) {
     return window['go']['main']['App']['ListFiles'](arg1);
 }