Worker: interactive terminal WebSocket bridge (PTY in workspace container)

- attachTerminalServer() upgrades /jobs/:id/terminal WS connections, verifying a
  short-lived job-scoped HMAC token (verifyTerminalToken) so the browser never
  holds the worker secret
- Bridges the socket to a bash PTY via dockerode exec (Tty) in a persistent
  per-job shell container (spoon-agent-term-<id>) mounting the workspace; binary
  frames = stdin, JSON text frames = resize; idle containers reaped after 30m
- New env: SPOON_AGENT_TERMINAL_IMAGE/SECRET/IDLE_MS (secret falls back to the
  shared worker internal token)

apps/agent-worker/src/worker.ts

@@ -1462,6 +1462,17 @@ export const runWorkspaceCommand = async (jobId: string, command: string) => {
   return { success: true };
 };
 
+// Non-throwing accessor for the interactive terminal: returns the active
+// workspace's mount info, or null when the workspace is not active here.
+export const getTerminalWorkspace = (jobId: string) => {
+  const workspace = activeWorkspaces.get(jobId);
+  if (!workspace) return null;
+  return {
+    workdir: workspace.workdir,
+    secrets: workspace.claim.secrets,
+  };
+};
+
 export const getWorkspaceAgentStatus = (jobId: string) => {
   const workspace = resolveWorkspace(jobId);
   return {