feat(maestro): rename a session from the web sidebar

Right-clicking a card opens a custom context menu (rename, spawn similar,
kill). Rename swaps the name for an inline field; Enter commits, Escape and
blur cancel. The tree stops rebuilding while the field is open, so a catalog
delta cannot replace what is being typed into.

Refs #125

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

web/src/api.ts

@@ -44,6 +44,20 @@ export async function createSession(req: CreateSessionRequest): Promise<Session>
   );
 }
 
+/** Rename a session (#125). An empty name clears the custom one, so the card
+ * falls back to the command. The daemon trims and caps what it stores and
+ * broadcasts the update, so callers need not patch the store themselves. */
+export async function renameSession(id: Uuid, name: string): Promise<Session> {
+  return jsonOrError(
+    await fetch(routes.session(id), {
+      method: "PATCH",
+      credentials: "same-origin",
+      headers: { "content-type": "application/json" },
+      body: JSON.stringify({ name }),
+    }),
+  );
+}
+
 export async function killSession(id: Uuid): Promise<void> {
   await jsonOrError(
     await fetch(routes.session(id), {