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>

web/src/connection.js

@@ -1,6 +1,6 @@
 import {
   Server, LIST_ARG, decodeServer, encodeBinaryInput, encodeCommand, encodeInit,
-  encodeInput, encodeResize, parseListOutput, tokenUrl, wsUrl, FlowControl,
+  encodeInput, encodeResize, parseListOutput, stripAnsi, tokenUrl, wsUrl, FlowControl,
 } from './protocol.js';
 
 export class AuthExpiredError extends Error {}
@@ -94,16 +94,17 @@ export class TtydConnection {
   }
 }
 
-// Ask the server for sessions + projects: a short-lived `devdesk attach --list`.
-export async function fetchSessionList(timeoutMs = 8000) {
+// Run a short-lived `devdesk attach <args…>` and return its output as text.
+// ttyd is the only server-side endpoint, so session actions travel this way.
+export async function runCommand(args, timeoutMs = 8000) {
   const token = await fetchToken();
   return new Promise((resolve, reject) => {
-    const socket = new WebSocket(wsUrl(window.location, LIST_ARG), ['tty']);
+    const socket = new WebSocket(wsUrl(window.location, args), ['tty']);
     socket.binaryType = 'arraybuffer';
     const chunks = [];
     const timer = setTimeout(() => {
       socket.close();
-      reject(new Error('session list timed out'));
+      reject(new Error('devdesk did not answer'));
     }, timeoutMs);
     socket.onopen = () => socket.send(encodeInit(token, 240, 24));
     socket.onmessage = (event) => {
@@ -113,16 +114,25 @@ export async function fetchSessionList(timeoutMs = 8000) {
     socket.onerror = () => {};
     socket.onclose = () => {
       clearTimeout(timer);
-      try {
-        const text = new TextDecoder().decode(concat(chunks));
-        resolve(parseListOutput(text));
-      } catch (err) {
-        reject(err);
-      }
+      resolve(new TextDecoder().decode(concat(chunks)));
     };
   });
 }
 
+// Sessions, projects and per-session Claude context (`devdesk attach --list`).
+export async function fetchSessionList() {
+  return parseListOutput(await runCommand([LIST_ARG]));
+}
+
+// `devdesk attach --new|--rename|--end …`: resolves on {"ok":true}, otherwise
+// rejects with devdesk's own error message.
+export async function sessionAction(action, ...args) {
+  const output = stripAnsi(await runCommand([`--${action}`, ...args])).trim();
+  if (/"ok"\s*:\s*true/.test(output)) return;
+  const message = output.split(/\r?\n/).filter(Boolean).pop() || 'no response';
+  throw new Error(message.replace(/^devdesk:\s*/, ''));
+}
+
 function concat(chunks) {
   const total = chunks.reduce((n, c) => n + c.length, 0);
   const out = new Uint8Array(total);