Share files and folders with the desktop file chooser (#6707)

Sharing a file or folder over LocalSend opened a terminal to run an fzf
pick over a find of the whole home directory, which is slow on a large
home, shows no previews, and looks nothing like the rest of the desktop.
The portal chooser is already how the other pickers here ask.

The chooser has a directory mode, so folder sharing asks for one the same
way, and neither entry needs a terminal to host a picker anymore.

A chooser that never opens is told apart from nobody picking anything, so
a portal failure says so rather than passing for a cancelled share.

Co-authored-by: Claude Opus 5 <noreply@anthropic.com>

default/omarchy/omarchy-menu.jsonc

@@ -77,8 +77,8 @@
   "trigger.reminder.show": {"icon":"󰢌","label":"Show all","action":"omarchy-reminder show"},
   "trigger.reminder.clear": {"icon":"󰢌","label":"Clear all","action":"omarchy-reminder clear"},
   "trigger.share.clipboard": {"icon":"","label":"Clipboard","action":"omarchy-menu-share clipboard"},
-  "trigger.share.file": {"icon":"","label":"File","action":"xdg-terminal-exec --app-id=org.omarchy.terminal bash -c 'omarchy-menu-share file'"},
-  "trigger.share.folder": {"icon":"","label":"Folder","action":"xdg-terminal-exec --app-id=org.omarchy.terminal bash -c 'omarchy-menu-share folder'"},
+  "trigger.share.file": {"icon":"","label":"File","action":"omarchy-menu-share file"},
+  "trigger.share.folder": {"icon":"","label":"Folder","action":"omarchy-menu-share folder"},
   "trigger.share.receive": {"icon":"󰥦","label":"Receive","action":"uwsm-app -- localsend"},
   "trigger.toggle.idle-lock": {"icon":"󰅶","label":"Stay Awake","action":"omarchy-toggle-idle"},
   "trigger.toggle.notifications": {"icon":"󰂛","label":"Notifications","action":"omarchy-toggle-notification-silencing"},