feat(desktop): worktree-aware sidebar grouping + composer/sidebar UX fixes

Group recents as parent-repo → worktree → sessions using local git
metadata (probed over IPC, with a path-name heuristic fallback for
remote backends). Single-worktree repos collapse to one level. Sessions
order by creation time and never reshuffle on new messages.

Also: fuse the status stack to the composer border, restore icon actions
in the queue panel, fix sidebar label truncation and drag styling, hide
sticky-message attachments while pinned, and bump the terminal font.

apps/desktop/electron/preload.cjs

@@ -54,6 +54,7 @@ contextBridge.exposeInMainWorld('hermesDesktop', {
   getRecentLogs: () => ipcRenderer.invoke('hermes:logs:recent'),
   readDir: dirPath => ipcRenderer.invoke('hermes:fs:readDir', dirPath),
   gitRoot: startPath => ipcRenderer.invoke('hermes:fs:gitRoot', startPath),
+  worktrees: cwds => ipcRenderer.invoke('hermes:fs:worktrees', cwds),
   terminal: {
     dispose: id => ipcRenderer.invoke('hermes:terminal:dispose', id),
     resize: (id, size) => ipcRenderer.invoke('hermes:terminal:resize', id, size),