refactor(e2b): drop speculative cleanup retry state

packages/e2b/subprocess-e2b/README.md

@@ -11,7 +11,7 @@ E2B implementation of the [`@deepseek-ai/dsh-subprocess`](../../subprocess/subpr
 - **Linux process groups** — a quoted wrapper starts each argv under `exec setsid --wait` and records its actual process-group id plus private status files beneath `ctx.e2b.runtimeRoot/processes`. The handle waits for that file instead of treating the SDK command PID as its published identity. Termination signals the negative recorded id with `SIGTERM`, waits the caller's `graceMs`, then escalates to `SIGKILL` and the SDK kill fallback; TERM delivery or probe failures also force that escalation. Process-table probes treat groups containing only zombie or dead entries as quiescent. Force cleanup succeeds only after a bounded probe finds the group empty; otherwise `waitForExit()` exposes a retryable failure, while proven quiescence makes later termination a no-op. Publication and monitoring failures apply the same cleanup transaction before rejecting. Service disposal rejects new starts, terminates and joins every retained process group, then awaits SDK settlement and private cleanup before the sandbox owner disposes.
 - **Environment boundary** — one trusted control-shell probe resolves the sandbox user's login home from its passwd entry and transports the sandbox environment as base64 ASCII for one strict UTF-8 decode; the wrapper then removes ambient `DSH_*` and credential-shaped (`*KEY*`, `*SECRET*`, `*TOKEN*`) names and restores every valid `spec.env` entry as an explicit caller opt-in. Empty names, `=`, and NUL framing violations reject before launch. Subsequent E2B command and PTY login shells receive a fresh randomized root-level `HOME` plus empty overrides for every scrubbed ambient name before user profiles can run; the requested argv receives the serialized environment afterward without changing the sandbox user's umask. Host ambient variables never enter the sandbox implicitly. Private environment files are removed after consumption, and failed command or terminal setup removes its private state before rejecting.
 - **Stdio projection** — the remote wrapper branches raw bytes into optional bounded spill files, frames each live chunk as newline-delimited base64 ASCII, and the host incrementally restores bytes across arbitrary SDK callback boundaries. Pipe mode writes those bytes to host Node streams; inherit mode writes them to the harness process streams; collect mode retains a bounded host tail with offset reads. The wrapper publishes the direct command status before waiting for inherited writers. For collect or inherit output, the adapter disconnects an incomplete SDK stream after `graceMs`, withholds its partial spill, and returns that status while retaining the remote group for `waitForExit()` and termination. Natural raw-pipe completion instead awaits lossless transport and preserves backpressure; explicit termination destroys the host pipes and releases blocked output before remote cleanup. Batch and streaming stdin use the SDK handle.
-- **Terminal sessions** — `spawnTerminal()` uses E2B's byte PTY API, installs the exact argv and scrubbed environment through private mode-`0600` files, reports the foreground process group, sends real signals, and tears down every live group in the remote terminal session through one retryable awaited `terminate()`; termination rejects new handle operations, aborts and joins in-flight writes, inspections, and signals, and treats zombie-only groups as quiescent. A private random output boundary discards the E2B bootstrap shell's prompt and echoed runner command while preserving every requested-process byte, including its first prompt. PTY allocation is awaited through handle publication before cancellation is observed, so owned rollback can clean the published handle. Setup and teardown own the private state transaction, abort pending setup during service disposal, fence publication, and retain an unproven setup cleanup for disposal retry. Prompt detection, scrollback, readiness, and owner policy remain in `dsh-pty-local`.
+- **Terminal sessions** — `spawnTerminal()` uses E2B's byte PTY API, installs the exact argv and scrubbed environment through private mode-`0600` files, reports the foreground process group, sends real signals, and tears down every live group in the remote terminal session through one retryable awaited `terminate()`; termination rejects new handle operations, aborts and joins in-flight writes, inspections, and signals, and treats zombie-only groups as quiescent. A private random output boundary discards the E2B bootstrap shell's prompt and echoed runner command while preserving every requested-process byte, including its first prompt. PTY allocation is awaited through handle publication before cancellation is observed, so owned rollback can clean the published handle. Setup and teardown own the private state transaction, abort pending setup during service disposal, and fence publication; sandbox disposal or timeout bounds a setup rollback that also fails. Prompt detection, scrollback, readiness, and owner policy remain in `dsh-pty-local`.
 - **Sandbox disappearance** — `SandboxNotFoundError` during process or terminal liveness, termination, rollback, or disconnect proves the remote execution world cannot retain work, so cleanup treats it as quiescent; unrelated failures remain observable.
 
 The default E2B base image supplies the runtime and Bash/GNU utilities this adapter invokes: `node`, `bash`, `setsid`, `ps`, `awk`, `tr`, `env`, `base64`, `chmod`, `tee`, `head`, `rm`, `kill`, `id`, and `getent`.