The Store install of Claude Desktop lives under
%LOCALAPPDATA%\Packages\Claude_<publisher-id>\, and its "AppData\Roaming"
is virtualised to LocalCache\Roaming inside that package. The classic
%APPDATA%\Claude\ folder is never read by the Store app, so a
claude_desktop_config.json dropped there is invisible to it; Theseus's
old existence check against path.dirname of that classic path was both
false-negative (nothing in classic, Store present) and false-positive
(empty classic folder left over, Store the real install) — the user saw
"Not installed on this computer" with Claude Desktop clearly running.
desktopConfigPath now looks for a Claude_<id> package first and uses
its LocalCache\Roaming\Claude path when present; otherwise it falls back
to the classic path. Added a desktopInstalled() helper that treats any
of: the config dir, a Store package, %LOCALAPPDATA%\AnthropicClaude,
%LOCALAPPDATA%\Programs\Claude, or Program Files\Claude as proof of an
install. register() mkdirSyncs the chosen path so the Store case
succeeds on first write.