feat(skill): spawn and drive DeepSeek Harness workers

The agent skill could spawn a worker in any mode, but it could only
DRIVE a claude one: every other CLI has neither a real end-of-turn
signal nor an answer to read, so the recipes route them through output
markers.

dsh has both halves now -- its harness reports idle/working/blocked to
Codeman, and the previous commit reads its transcript -- so it joins
claude as a mode the four verbs work on unchanged. `spawn_workers alpha
beta:deepseek` is a mixed fleet in one call, and `sendwait` / `last_text`
/ `delete_session` need no per-mode variant.

Preamble 1.20.0 (SKILL.md's §0 heredoc regenerated from it):

- `spawn_worker` grows a deepseek branch that gates on the harness
  composer. ⚠️ Readiness there is NOT the stop signal: the harness
  reports idle at BOOT ~300 ms before its composer paints (measured
  2.26 s vs 2.56 s after spawn), so a send-and-wait fired straight after
  quick-start resolves on the boot edge, reports a turn that never ran,
  and strands the prompt in a pane not yet taking input. Waiting for the
  composer also spends that edge, since signals are edge-triggered.
- `spawn_workers` takes `name[:mode]`, so a mixed fleet stays one
  concurrent call. Case names still have to be unique -- the mode never
  disambiguates two workers that would share a directory.
- `sendwait` asks for `wait:"stop,exit"` instead of the `wait:true`
  default set. That set also carries `idle`, which for an external CLI is
  inferred from output stabilization: on a dsh worker whose TUI repaints
  rarely, the re-wait resolved in 0 ms with `signal:"idle"` on a turn
  with three minutes left to run. It also makes a wrong mode loud -- the
  modes that cannot deliver `stop` answer 400 before writing anything,
  instead of resolving on a flap.
- The self-heal resend carries `delivered:true` forward. The resend is a
  tagged duplicate, so the server truthfully reports `delivered:false`
  about a write it skipped, and §1's cleanup then read a completed turn
  as an undelivered one and kept a finished worker forever.
- dsh workers spawn with the permission posture the Run button sends,
  because the harness default still asks and a worker parked on an
  approval row cannot finish a fan-out. The multi-user clamp still
  applies.

Docs: a worked dsh flow in recipes.md, readiness and the signal rules in
verbs.md, and the corrections this makes necessary -- `stop`/`blocked`
are no longer claude-only, and `last-response` is no longer permanently
empty for deepseek. The integration guide gains a section on reading a
session back and driving one as a worker; its web-UI section was also
stale (that server moved out of a shell session).

The static guard that keeps those lists from naming some external CLIs but
not others is extended rather than exempted: it now knows the three real
classes inside that family (no transcript, no hook signals, and the
positive twin -- the modes whose answers can be read), with the hook class
derived from `hooksAvailableForMode()` so the predicate and the prose
cannot drift apart. Any other partial list still fails, and a new backend
belongs to none of the classes until someone says so.

docs/architecture-invariants.md

@@ -32,6 +32,10 @@ Implementation detail extracted from `CLAUDE.md` so that file stays small enough
 
 ⚠️ **`agent_working` is a hook event with no Claude Code hook behind it** (157th SSE constant). It exists because a harness turn cannot run while one of its own modal approvals is on screen, so "the agent started working" proves a dialog was answered in the terminal. It joins `APPROVAL_RESOLVING_EVENTS`; without it a dsh session's red alert would survive until the next `stop`, the exact stuck-alert bug the claude path already had to fix once — and the pane-capture staleness sweep that fixed it there is Claude-dialog-shaped and cannot help here.
 
+⚠️ **Answers are READ FROM DISK for this mode, not scraped off the pane** (`src/deepseek-transcript.ts`, behind `GET /api/sessions/:id/last-response`). dsh writes a structured JSONL transcript at `$DSH_HOME/sessions/<mangled-cwd>/<dsh-session-id>/session.jsonl.zstd`, so it belongs with claude and codex rather than with the pane-segmented modes — and for dsh specifically the segmenter was not merely coarse but WRONG: dsh-TUI paints a full-screen splash, so a `last-response` call on a fresh dsh session returned its ASCII-art logo, which anything polling for a worker's first answer reads as an answer. Four mechanisms in that file are load-bearing. **(1)** dsh appends **one zstd FRAME per write**, and Node's `zlib` zstd decoder — one-shot AND streaming — stops at the first frame end: a real 56-line transcript decoded as 1 line / 158 bytes, i.e. the session header alone, so every call would have reported "nothing said yet" forever. `zstdFrameRanges()` walks frame and block headers (no decompression) to find exact boundaries and decompresses each frame; splitting on the 4-byte magic instead would corrupt everything after a magic sequence that happens to occur inside compressed data. zstd itself is resolved at RUNTIME (`zstdSupported()`), because it landed in Node 22.15 while the project floor is 22.0 and `@types/node` still does not declare it; without it the mode falls back to the pane exactly as before, which is why `readDeepSeekLastResponse()` distinguishes `null` ("this reader cannot run here") from an empty result ("read fine, nothing said yet"). **(2)** Every turn also records a plugin-sourced `user/message` (dsh's runtime-context snapshot: sandbox policy, approval policy, cwd), so only `source.kind === 'user'` is a real prompt. **(3)** A turn that ends in `reason.kind: 'error'` is surfaced as `Turn error: …` (and a non-error early stop such as `max-tokens` as `Turn ended: …`) rather than as an empty string, which an agent reads as "still thinking" through fifteen polls. **(4)** Reply text is assembled per (turn, step): a finalized `assistant/message` wins, and the streamed `assistant/chunk` / `text-chunks` deltas are consulted ONLY for a step that never finalized (so a partial answer is readable mid-turn without ever being appended twice) — ⚠️ and "finalized" is tracked as a SET of steps, not as non-empty text, because a step whose whole reply was reasoning strips to `''` at the `</think>` boundary and would otherwise resurrect the raw, unstripped deltas in its place (measured on a real conversation). ⚠️ Session→transcript pairing is by the transcript's own header `cwd` plus a ±60 s boot window against the Codeman session's `createdAt`, never by reproducing dsh's directory mangling (which already has two forms on disk, `<uuid>` and `session-<uuid>`) and never by newest-mtime alone: mtime alone handed a freshly spawned worker its PREDECESSOR's answer in the same case directory, which is worse than saying nothing because an agent cannot tell a stale answer from a fresh one. The `DSH_HOME` override reaches the reader through the narrow `Session.deepSeekHomeOverride` getter rather than an `envOverrides` accessor, since that map can hold provider credentials; it is ephemeral by design (never persisted), so a session that overrode it and outlived a server restart resolves the default tree and reads as "nothing said yet". Tests: `test/deepseek-transcript.test.ts`.
+
+⚠️ **This is also what makes dsh the one non-claude mode the `codeman` agent skill drives like claude** (`skills/codeman/preamble.sh`, preamble 1.20.0): with a real end-of-turn signal AND a real transcript, `spawn_workers alpha beta:deepseek` is a mixed fleet in one call and `sendwait`/`last_text` need no per-mode variant. Two traps are handled in the preamble rather than left to the agent. **Readiness is not the stop signal**: the harness reports `idle` at BOOT roughly 300 ms before its composer paints (measured 2.26 s vs 2.56 s after spawn, twice), so a send-and-wait fired straight after `quick-start` resolves on the boot edge, reports a turn that never ran, and strands the prompt in a pane that was not yet accepting input — `spawn_worker`'s dsh branch gates on the composer glyph (`❯`, overridable via `DSH_READY_MARK`) instead, after which the boot edge is spent and unobservable. And `sendwait` asks for `wait:"stop,exit"` rather than the `wait:true` default set, because that set also carries `idle`, which for any external CLI is inferred from output stabilization: on a dsh worker whose TUI repaints rarely, a re-wait resolved in 0 ms with `signal:"idle"` on a turn that had three minutes left to run. The skill also sends `deepSeekConfig.permissionMode: 'danger-full-access'` for its own workers, matching what the Run button sends, because the harness default still asks and a worker parked on an approval row cannot finish a fan-out (the multi-user clamp still applies).
+
 ⚠️ **The resolver needs the strictest identity probe of any CLI**, because `dsh` is not merely a squattable npm name: Debian ships an unrelated `dsh` (dancer's shell, `apt install dsh`) that would answer a version probe convincingly. `probeDeepSeekVersion()` therefore checks `dsh --help` against `DEEPSEEK_IDENTITY_REGEX` (`DeepSeek Harness`) FIRST and only then reads a version, and `test/deepseek-cli-resolver.test.ts` pins both the rejection and the VITEST hermeticity gate with a real executable fixture. `DEEPSEEK_VERSION_REGEX` keeps the prerelease tail (`0.1.1-rc.2`), since truncating it would report an rc as a release; it is shared with the `dsh` dependency-registry entry so doctor and run mode agree about the version even though the resolver is stricter about identity.
 
 Model is NOT a session field: it is a composition entry in the profile's config tree (`agent-default-model`), configured in `~/.dsh/settings.yaml` + `cordis.patch.yml`, so both create paths deliberately resolve no model for this mode. Env allowlist: `DSH_*` + `DEEPSEEK_*`; provider keys named by a settings-file `apiKeyEnv` stay OUT, which is pi's 34-provider-key problem in a new shape and gets the same answer. Docker seeds `~/.dsh` per-file (`.env`, `settings.yaml`, `cordis.patch.yml`) and the image installs its OWN profile, because `profiles/` is a per-profile `node_modules` tree — host-arch-specific and far too large to copy per container start. Stays OUT of `isAltScreenStripMode()` (third-party fullscreen TUI — the opencode case). ⚠️ `classifyProfile()` reads the profile's BUNDLES, and "unknown means launchable" is deliberate (anyone can publish an app bundle), but it has one knowably-wrong case: `readProfile()` returns an empty bundle list for a `package.json` with no `dsh.profile.bundles`, which made the SHIPPED `web`/`headless` profiles look third-party and launchable. The directory name is therefore consulted as a LAST resort (`STOCK_NON_INTERACTIVE_PROFILES`), after the bundle patterns, so real bundle evidence always wins over a name the user chose. The loose `tui` arm carries word boundaries for the same reason: it decides which profile boots by default, and matching the middle of `intuition` is not a rule anyone could predict. ⚠️ The generated shim is written **temp + rename**, not in place: the TUI can be exec'ing that exact path while an upgraded Codeman refreshes it, and a half-written file is a syntax error the caller then retries four times per state change forever. Bump `SHIM_VERSION` whenever `SHIM_SOURCE` changes, or an existing shim keeps matching the embedded marker and is never refreshed. Availability via `GET /api/deepseek/status`, the widest per-CLI status shape (`available`/`runnable`/`path`/`version`/`dshHome`/`defaultProfile`/`profiles`); `POST /api/deepseek/install-profile` bootstraps a profile and is the only endpoint in Codeman that installs third-party code — regex-confined specifier, argv-array spawn, privileged grant required in multi-user mode, and the held-open request is bounded by a HAND-ROLLED timeout over a `detached: true` process group (negative-pid SIGTERM→SIGKILL, as `runGit()` does in git-clone.ts). ⚠️ Node's own `spawn` `timeout` is NOT enough: a plugin install fans out into package-manager children, the built-in timeout signals only the direct child, and the survivors hold the inherited stdio pipes open so `close` never fires and the request leaks forever. User guide: `docs/deepseek-integration.md`. Tests: `test/deepseek-mode.test.ts`, `test/deepseek-cli-resolver.test.ts`.