fix(sessions): scope the launch model to claude and pin it with the advisor (#514, #515, #530 landing)

Maintainer merge-time fixes for the three PRs that landed together on the
session create / launch / persistence path.

#514 findings (bot verdict merge-with-fixes):
- minor, fixed: SessionState.model was published and persisted for every
  mode, so a codex/opencode cron session reported the app-wide Claude
  default it never ran on. toState() now emits it only where the new
  cliTakesSessionModel() holds (registry capability model.source ===
  'claude-settings-file', no CLI id branch). POST /api/sessions uses the
  same helper for its non-claude refusal, so refusal and publication cannot
  drift. Recovery then hands back undefined for other modes on its own.
- nit, fixed: the `model` schema admitted a leading dash (and '.', '[').
  The first character must now be a letter or digit; still a subset of the
  registry's model-claude pattern, so nothing accepted is refused at launch.
- nit, fixed (reject, the consistent choice): `model` with
  attachRemoteSession was silently dropped. Now a 400 INVALID_INPUT, as
  #514 does for non-claude CLIs and quick-start does for remote cases.
  advisorModel (#530) gets the same refusal there. effort and envOverrides
  keep their older silent ignore on that branch so no existing caller breaks.

#515 finding (bot verdict merge, one nit):
- nit, fixed: the types/session.ts @fileoverview described CodexConfig as
  (model, resumeSessionId); it now lists reasoningEffort, bypass,
  animations and renderMode too.

Audit of the merged combination (not reviewed before):
- The conflict resolutions in session.ts (toState), types/session.ts,
  reboot-restore-routes.ts, server.ts (restoreMuxSessions), CLAUDE.md and
  skills/codeman/reference/endpoints.md (+ plugin mirror) keep both sides
  correctly; nothing was lost or doubled.
- A claude session with both `model` and `advisorModel` launches with
  `--model <id>` and ONE merged `--settings` JSON (ultracode + advisorModel,
  or advisorModel beside `--effort <level>`), on the tmux template
  (including the resume || new variant and with the statusLine exporter)
  and on the direct-PTY fallback. Both values (and effort) survive
  restoreMuxSessions onto a dead pane, a reboot restore into a fresh pane,
  and restartCli/dead-pane respawn via _buildRespawnPaneOptions.
- quick-start and ralph-loop take no per-session `model` (matching #514's
  scope, POST /api/sessions only) and launch on the app-wide default, which
  toState now persists for claude, so recovery stays consistent.
- No defect found in the combination beyond the findings above. Noted, not
  changed: advisorModel is still published for any mode a caller sends it
  with (launch-inert there; the UI and skill send it for claude only).

Tests: test/session-model-recovery.test.ts pins the pair through both
recovery shapes for effort ultracode/high/none, the recovery constructors'
fields, the tmux-manager builder hop, and the codex/opencode/shell
non-publication; test/advisor-model.test.ts pins the launch lines and a
real direct-PTY Session's pty.spawn argv; the route test covers flag-shaped
models, attach refusals and the published fields. Docs: SessionState.model
docstring, the reboot-restore-registry header, the golden test comment and
the CLAUDE.md model/advisor bullets.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

CLAUDE.md

@@ -137,8 +137,8 @@ Codeman is a Claude Code session manager with web interface and autonomous Ralph
 - **Global regex `lastIndex`** — Shared `g`-flag patterns in loops must reset `lastIndex = 0` first, or use the `execPattern()` helper in `utils/regex-patterns.ts` (resets automatically)
 - **`envOverrides` flow `CLAUDE_CODE_*` / `OPENCODE_*` / `CODEX_*` / `GEMINI_*` / `GOOGLE_*` / `ANTIGRAVITY_*` / `PI_*` / `GROK_*` / `XAI_*` / `DSH_*` / `DEEPSEEK_*` env vars, plus exact-key `CLAUDE_CONFIG_DIR`** — Set via `POST /api/sessions { envOverrides }`, stored on `Session._envOverrides`, exported by `tmux-manager.buildEnvExports()` at spawn time, persisted in `SessionState.envOverrides`. **Do NOT** write these to `<case>/.claude/settings.local.json` — that's the old path and creates UI/disk drift. (`GOOGLE_*` is the deliberately-broad Vertex-AI namespace for Gemini — see Multi-CLI prefix discipline.) `CLAUDE_CONFIG_DIR` (#255, exact match via `ALLOWED_ENV_KEYS` in `schemas.ts`) points a session at a separate Claude account/config dir for per-client subscriptions; it persists to state.json (a path, not a secret; losing it on restart would silently switch accounts). ⚠️ A relocated config dir writes transcripts outside `~/.claude/projects`, so the response viewer, subagent windows, ultracode panel and Read My Mind capture go blind for that session unless the user symlinks `projects` back into the shared tree (`ln -s ~/.claude/projects <configDir>/projects`). ⚠️ It is also one of claude's `privilegedEnvKeys` (Custom Model Endpoint Profiles, since it can redirect a session's traffic same as any other injected var), so in multi-user mode setting it via `envOverrides` is admin-only, and a non-granted owner's already-persisted `CLAUDE_CONFIG_DIR` is stripped on reboot-restore — silently returning that session to the default Claude account rather than the one it was pointed at (see `session-env-clamp.ts`). → [architecture-invariants#per-session-env-overrides-exact-key-allowlist-and-claude_config_dir](docs/architecture-invariants.md#per-session-env-overrides-exact-key-allowlist-and-claude_config_dir)
 - **Effort is NOT an env var** — never carry effort as `CLAUDE_CODE_EFFORT_LEVEL`: the env var hard-locks effort and blocks in-session `/effort` switching (incl. ultracode). It flows as the dedicated `effort` payload field → `Session._effort` → `claude --effort <level>` for regular levels incl. `max` (the settings `effortLevel` key is `enum(["low","medium","high","xhigh"]).catch(undefined)` — `max` gets SILENTLY dropped there), or `claude --settings '{"ultracode":true}'` for ultracode (rejected by `--effort`). Both are soft defaults the user can override anytime. Legacy env-var entries are auto-migrated by the Session constructor and unset from tmux sessions in `applyEnvOverrides()`. See `buildEffortCliArgs()` in `session-cli-builder.ts`, tests in `test/effort-injection.test.ts`
-- **The advisor rides `--settings`, NEVER the `--advisor` flag**: Claude Code's advisor tool (a stronger model consulted at decision points, code.claude.com/docs/en/advisor) flows as the `advisorModel` payload field → `Session._advisorModel` (persisted, so respawn and reboot restore keep it) → the `advisorModel` key in the launch's ONE `--settings` JSON, merged with ultracode and the statusLine exporter by `buildAdvisorSettings()` (`session-cli-builder.ts`). ⚠️ The flag EXITS at launch on any pairing the CLI refuses (`claude --advisor haiku` exits 1, so does Fable before its usage-credit consent), which would leave a dead pane on every respawn; the settings key degrades to "no advisor" instead. ⚠️ `isAdvisorModel()` (fable/opus/sonnet aliases or full ids, no haiku) is also the injection guard for the single-quoted argument. Soft default: `/advisor` still switches it in-session. App Settings key `claudeAdvisorModel` (SYNCED, `''` = leave it to the CLI). Remote/docker quick-start refuses it, like `effort`. Tests: `test/advisor-model.test.ts`
-- **Model choice: a persistent default in `settings.local.json`, a per-session `--model`, never env** — the App Settings **Claude Model** picker (`claudeModel` in `settings.json`) is read by `session-ui.js` at session create (wins over the legacy 1M-Opus toggles `opusContext1m`/`opusContext1mEnabled`), sent as the `modelOverride` payload field, and `updateCaseModel()` (`hooks-config.ts`) writes/deletes the `model` key in `<case>/.claude/settings.local.json`. This is the intended exception to the envOverrides rule above: model legitimately lives in `settings.local.json` (a soft default — in-session `/model` still works); env vars do not. A caller that wants one session on a model without touching the case sends `model` on `POST /api/sessions` instead: it goes out as `claude --model <id>`, writes nothing, wins over the app-wide default, and is persisted as `SessionState.model` so both recovery paths relaunch on it (`test/routes/session-routes-claude-model.test.ts`, `test/session-model-recovery.test.ts`).
+- **The advisor rides `--settings`, NEVER the `--advisor` flag**: Claude Code's advisor tool (a stronger model consulted at decision points, code.claude.com/docs/en/advisor) flows as the `advisorModel` payload field → `Session._advisorModel` (persisted, so respawn and reboot restore keep it) → the `advisorModel` key in the launch's ONE `--settings` JSON, merged with ultracode and the statusLine exporter by `buildAdvisorSettings()` (`session-cli-builder.ts`). ⚠️ The flag EXITS at launch on any pairing the CLI refuses (`claude --advisor haiku` exits 1, so does Fable before its usage-credit consent), which would leave a dead pane on every respawn; the settings key degrades to "no advisor" instead. ⚠️ `isAdvisorModel()` (fable/opus/sonnet aliases or full ids, no haiku) is also the injection guard for the single-quoted argument. Soft default: `/advisor` still switches it in-session. App Settings key `claudeAdvisorModel` (SYNCED, `''` = leave it to the CLI). Remote/docker quick-start refuses it, like `effort`, and so does a remote attach on `POST /api/sessions`. Tests: `test/advisor-model.test.ts`
+- **Model choice: a persistent default in `settings.local.json`, a per-session `--model`, never env** — the App Settings **Claude Model** picker (`claudeModel` in `settings.json`) is read by `session-ui.js` at session create (wins over the legacy 1M-Opus toggles `opusContext1m`/`opusContext1mEnabled`), sent as the `modelOverride` payload field, and `updateCaseModel()` (`hooks-config.ts`) writes/deletes the `model` key in `<case>/.claude/settings.local.json`. This is the intended exception to the envOverrides rule above: model legitimately lives in `settings.local.json` (a soft default — in-session `/model` still works); env vars do not. A caller that wants one session on a model without touching the case sends `model` on `POST /api/sessions` instead: it goes out as `claude --model <id>`, writes nothing, wins over the app-wide default, and is persisted as `SessionState.model` so both recovery paths relaunch on it (`test/routes/session-routes-claude-model.test.ts`, `test/session-model-recovery.test.ts`). ⚠️ Claude only, via the `model.source` capability (`cliTakesSessionModel()`), never a mode check: refused for other CLIs and on a remote attach, and published by `toState()` for claude alone (cron hands its Claude default to every CLI with a model).
 - **Multi-CLI prefix discipline** — env-var prefix is CLI-specific (`CLAUDE_CODE_*` vs `OPENCODE_*` vs `CODEX_*` vs `GEMINI_*` vs `ANTIGRAVITY_*` vs `PI_*` vs `GROK_*` vs `DSH_*`) and the `ALLOWED_ENV_PREFIXES` allowlist in `schemas.ts` enforces this; non-prefix exceptions are exact keys in `ALLOWED_ENV_KEYS` (currently only `CLAUDE_CONFIG_DIR`), never a widened prefix. Gemini additionally allowlists the **broad `GOOGLE_*`** namespace (intentional: Vertex AI auth needs `GOOGLE_CLOUD_PROJECT`/`GOOGLE_APPLICATION_CREDENTIALS`/`GOOGLE_GENAI_USE_VERTEXAI`; it is the loosest allowlist entry, affecting only the user's own spawned CLI), and Grok allowlists **`XAI_*`** for the same vendor-namespace reason (`XAI_API_KEY` is grok's documented auth var). When adding a setting, decide which CLI(s) it applies to and gate the env export accordingly. Never blanket-forward all prefixes. ⚠️ Pi is the case that proves the rule: its ~34 provider keys (`ANTHROPIC_API_KEY`, `OPENAI_API_KEY`, `HF_TOKEN`, …) share NO prefix, and the allowlist is one GLOBAL list applied by a refine with no mode context, so admitting them for pi would widen it for every mode at once — they stay out, and pi users authenticate via `/login` or the server process's own env. ⚠️ DeepSeek repeats pi's lesson exactly: a dsh `settings.yaml` can nominate ANY env var as a provider credential (`apiKeyEnv`), so only the vendor namespaces `DSH_*` (launcher inputs incl. `DSH_PERMISSION_MODE`) and `DEEPSEEK_*` (`DEEPSEEK_API_KEY`/`DEEPSEEK_BASE_URL`) are admitted; foreign provider keys authenticate from dsh's own files or the server env. Resolver design pattern: `docs/opencode-integration.md`, `docs/pi-integration.md`, `docs/grok-integration.md`, `docs/deepseek-integration.md`
 - **Zod `.optional()` rejects `null`** — accepts `undefined` only. When the frontend builds a request body with `JSON.stringify`, an explicit `null` field is preserved on the wire and fails validation with `INVALID_INPUT`. Convert `null` → `undefined` before stringifying (e.g. `field: value ?? undefined`), or declare the schema `.nullish()`. This has caused real shipped bugs twice
 - **Local-echo overlay stays on screen**: the overlay lays its wrapped lines out DOWNWARD from the prompt row, and the text has not reached the PTY yet, so the CLI never learns the prompt is long and nothing scrolls to make room. With the keyboard up only a handful of rows are visible, so a long prompt used to run off the bottom and the user typed blind. The block now grows UPWARD once it would pass the last visible row (optional `totalRows` in `RenderParams`; the line divs are opaque, so they cover transcript above), and a prompt taller than the viewport keeps its TAIL. ⚠️ Separately, `_shrinkPaddingToFit()` (mobile-handlers.js) must never shrink `main`'s padding-bottom below the MEASURED height of the fixed bars: on phones the toolbar and accessory bar are `position: fixed`, so that padding is the only thing reserving room for them, and taking it pulled the terminal's bottom row behind them. Tests: `packages/xterm-zerolag-input/test/overlay-renderer.test.ts`, `test/mobile-keyboard-bottom-padding.test.ts`.