feat: free-form sessions, rename/end from the panel, live Claude Context (0.2.0)

- Sessions no longer need a project folder: any name works and starts in
  DEVDESK_DEFAULT_DIR unless it matches a project; `devdesk new NAME [PROJECT]`.
- Rename (✎) and end/forget (×) sessions from the Sessions panel, plus
  `devdesk rename`. The browser runs them as `devdesk attach --new|--rename|--end`
  through ttyd. Renames keep the running Claude and its recorded conversation:
  the hook, the run-wrapper and the statusline ask tmux for the current name.
- Claude Context panel is live: devdesk-statusline snapshots model,
  context-window use, cost and edits per session, which --list reports;
  Claude's footer gets a one-line summary. The panel now sits under Sessions.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/DEPLOY.md

@@ -44,7 +44,9 @@ Enable the Proxmox firewall on CT 126 (`firewall=1` on net0) and allow tcp/7681
 |---|---|
 | Sessions | `devdesk ls` |
 | Attach over SSH | `devdesk attach <name>` (or `devdesk pick`) |
-| End a session | `devdesk end <name>` (or `[x]` in the Claude window's exit menu) |
+| New session (optionally in a project) | `devdesk new <name> [project]`, or the Sessions panel form |
+| Rename a session | `devdesk rename <old> <new>`, or ✎ in the Sessions panel |
+| End a session | `devdesk end <name>`, × in the Sessions panel, or `[x]` in the Claude window's exit menu |
 | Restart the web side (safe) | `systemctl restart devdesk` |
 | **Stop every session** | `systemctl stop devdesk-tmux` |
 | Logs | `journalctl -u devdesk -u devdesk-tmux` |