docs(local-model): name every covered launch path, both install executors, and the port without a login

The runner header says what each caller passes (the job: the compiled stock
command; the route: the merged entry, behind cliManagementEnabled).
docs/cli-registry.md names both executors in its trust boundary. The
security architecture gains a section on the pinned runtime and its hash,
the loopback port without a login and the digest check, and the install
path without cliManagementEnabled; SECURITY.md lists the port as a known
limitation. The guides and the rules name exactly the paths the launch
guard covers, the session that keeps calling a stopped runtime's port, the
claim before the connect writes, and the outcome kept in memory.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

docs/api-reference.md

@@ -1689,8 +1689,8 @@ Every route is admin only in multi-user mode (`403 FORBIDDEN`, answered before a
 | `GET`    | `/api/local-model`         | none                                             | `200` with `{ hardware, recommendation, catalogUpdated, install }`. `500 INTERNAL_ERROR` only when the recommendation itself fails, never for a failed probe.                                                                                             |
 | `POST`   | `/api/local-model/install` | `{ modelId, cli, context, acknowledgedBytes }`   | Starts the one install job and answers at once; the job runs on in the server. `400 INVALID_INPUT` when the three choices are not a row the server offers right now. `409`: `job-running`, `already-installed`, `size-changed`.                         |
 | `POST`   | `/api/local-model/cancel`  | none                                             | Interrupts the step in flight; the job is `paused` at that step. `409 wrong-state` when no job is running.                                                                                                                                                |
-| `POST`   | `/api/local-model/resume`  | `{ newPort? }` (may be absent)                   | Continues a `paused` or `failed` job at the same step. `newPort: true` chooses another port first. `409`: `job-running`, `wrong-state`.                                                                                                                  |
-| `POST`   | `/api/local-model/runtime` | `{ action: "start" \| "stop", newPort? }`        | `stop` stops the runtime and keeps it from starting at the next boot; `start` undoes that. `newPort: true` with `start` chooses another port and moves the saved endpoint to it. `409`: `job-running`, `wrong-state` (nothing is installed).            |
+| `POST`   | `/api/local-model/resume`  | `{ newPort? }` (may be absent)                   | Continues a `paused` or `failed` job at the same step. `newPort: true` chooses another port first. `409`: `job-running`, `wrong-state`, `sessions-open` (`newPort` while live sessions use the model).                                                  |
+| `POST`   | `/api/local-model/runtime` | `{ action: "start" \| "stop", newPort? }`        | `stop` stops the runtime and keeps it from starting at the next boot; `start` undoes that. `newPort: true` with `start` chooses another port and moves the saved endpoint to it. `409`: `job-running`, `wrong-state` (nothing is installed), `sessions-open` (`stop` or `newPort` while live sessions use the model: their agents keep calling the address they were started with). |
 | `DELETE` | `/api/local-model`         | `{ removeModel? }` (may be absent)               | Stops the runtime, removes the saved endpoint, restores the settings flag when this feature switched it on and no other endpoint is saved, deletes the runtime; the model only with `removeModel: true`. `409`: `job-running`, `sessions-open`.        |
 
 Every verb answers `{ success: true, data: <install> }` with the `install` object (below) as it is after the verb. A refusal the feature names is a `409` whose envelope also carries the conflict:
@@ -1711,7 +1711,7 @@ Every verb answers `{ success: true, data: <install> }` with the `install` objec
 
 `data.reason` is `job-running`, `already-installed` (remove the installed model first), `size-changed` (with `expectedBytes` and `expectedGb`), `sessions-open` (with `sessions`, the names of the live sessions that use the model) or `wrong-state`. A `409 CONFLICT` without `data` means a config file that must not be overwritten (`settings.json` or `custom-model-hosts.json` does not parse); `error` names the fix.
 
-`POST /api/local-model/install` also answers `400` when a saved model endpoint already uses the id `local-ollama` and was not created by this feature: rename or delete that endpoint first. The check is made before anything is downloaded.
+`POST /api/local-model/install` also answers `400` when a saved model endpoint already uses the id `local-ollama` and was not created by this feature: rename or delete that endpoint first. The check is made before anything is downloaded. Every `400` the install names, and the `507 OPERATION_FAILED` of a first install on a full disk, carries its sentence as `data.message` (`{ text, vars }`, like a `409`), so a client can print it in its own language.
 
 **Consent is bound to the size shown.** `acknowledgedBytes` must be the `installBytes` of the chosen row: the model download plus the runtime download while the runtime is not unpacked yet. The server compares it with its own total before anything starts and answers `409 size-changed` when they differ, so a click confirms exactly the size the person saw.