fix(desktop): respect local-origin tauri shell for directory access (#391)

* feat: enable local-origin desktop features and copy in terminal support

- Enable arbitrary web loads in desktop web content for TAURI apps.
- Guard directory dialog access behind local-origin origin check.
- Add copy-to-clipboard support for terminal selections via common shortcuts.

* fix: improve initial directory resolution and persistence in directory store

packages/ui/src/lib/desktop.ts

@@ -201,8 +201,8 @@ export const getDesktopHomeDirectory = async (): Promise<string | null> => {
 export const requestDirectoryAccess = async (
   directoryPath: string
 ): Promise<{ success: boolean; path?: string; projectId?: string; error?: string }> => {
-  // Desktop shell: use native folder picker.
-  if (isTauriShell()) {
+  // Desktop shell on local instance: use native folder picker.
+  if (isTauriShell() && isDesktopLocalOriginActive()) {
     try {
       const tauri = (window as unknown as { __TAURI__?: TauriGlobal }).__TAURI__;
       const selected = await tauri?.dialog?.open?.({