bug: opening a terminal whose command is not installed leaves a tab that can never be closed

### Against a real daemon on main

Same create_terminal / list_terminals / kill_terminal RPCs the app uses, isolated daemon (own PASEO_HOME, OS-assigned port). Ghosts accumulate, every kill reports success:


attempt 1: terminal ls --all -> [{"id":"d6d7a042-...","name":"Codex"}]
attempt 1: terminal kill d6d7a042-... -> success: true
attempt 1: terminal ls --all (after kill) -> ["d6d7a042-..."] stillListed=true
attempt 2: terminal kill 48e37c38-... -> success: true
attempt 2: terminal ls --all (after kill) -> ["d6d7a042-...","48e37c38-..."] stillListed=true
RESULT missing-binary: ghosts=7/10
RESULT fast-exit (process.execPath -e 'process.exit(0)'): ghosts=9/10


After 20 attempts: 16 unclosable "Codex" terminals. A working command on the same daemon was still created, listed and killed normally.

### Instrumented trace

Worker side:


CREATED <id> alreadyExited=true   # session already dead when watchTerminal subscribed
EXIT-CB <id>                      # onExit replay fired, terminalExit sent to the parent


Parent side, in received order:


RECV terminalCreated
REGISTER <id>                     # registered from the terminalCreated event
RECV response ok=true             # createTerminal response
RECV terminalExit <id>
EXIT-EVENT <id> hasRecord=true    # the exit found the record and removed it
REGISTER <id>                     # createTerminal's continuation re-registers the dead terminal


All three arrive in the same tick, so the awaiting createTerminal continuation runs after the exit was processed and registers the terminal a second time.

### Symptoms once a record is in that state

- `terminal ls --all --json` lists the id with `"cwd": "-"`; a live terminal shows a real path
- `terminal capture <id> -S --json` returns `{"lines": [], "totalLines": 0}`
- `terminal kill <id>` returns `success: true`, and re-listing still shows it
- `paseo daemon restart` clears it; the workspace's agent is unaffected

Production evidence, Paseo 0.2.5 Linux daemon: 3 "Codex" terminals with `cwd: "-"`, empty capture, `kill` returning `success: true` each, all gone after a daemon restart.

### What a missing command actually reports

Through `createTerminal` against a real pty (macOS 15, Node v24.13.0), full TerminalExitInfo:


1. missing binary  -> {"exitCode":1,"signal":null,"lastOutputLines":[]}
2. echo hi         -> {"exitCode":0,"signal":null,"lastOutputLines":["hi"]}
3. false           -> {"exitCode":1,"signal":null,"lastOutputLines":[]}
4. default shell   -> no exit within 1500ms (still running)


Cases 1 and 3 are identical. Paseo calls `pty.spawn` directly with no shell, so a missing binary is the node-pty spawn helper failing - no 127, no "command not found" text.

### Failing test

Replaying that message order through the existing FakeTerminalWorker in `packages/server/src/terminal/worker-terminal-manager.test.ts` reproduces it deterministically, on macOS and Linux:


x does not resurrect a terminal that exited before its create response was handled
AssertionError: expected { id: 'terminal-a', ...(21) } to be undefined
x replays the exit to a listener attached after a create that lost the race
AssertionError: expected [] to deeply equal [ { exitCode: +0 } ]