Add 9Router control plugin (#291)

* Add 9Router panel plugin

This commit introduces the initial version of the 9Router panel plugin.
It provides a Noctalia panel to manage 9Router model combos directly
from the bar, without requiring the web dashboard.

Key features:
- List, create, rename, and delete model combos.
- Reorder models within a combo via drag-and-drop.
- Change combo routing kind (fallback, round-robin, fusion).
- Search and filter combos.
- Supports 9Router dashboard authentication via CLI token or password.

Includes a bar widget showing connection status, a full UI panel,
and a background service to interact with the 9Router REST API.
Translations for English and Vietnamese are included.

* Rename 9Router Panel to 9Router Control

Update plugin IDs, IPC commands, and internal references.

* Quote shell args in service commands

Add shell_quote() for URLs, bodies, and file paths passed to
noctalia.runAsync. Declare required external commands in plugin.toml
and document them in the README.

9router-control/README.md

@@ -0,0 +1,84 @@
+# 9Router Control
+
+Manage your [9Router](https://github.com/decolua/9router) combos right from the
+Noctalia bar — no web dashboard needed.
+
+- **List combos** — see every combo with its model chain and routing kind.
+- **Reorder models** — open a combo and move models up/down to change fallback
+  order.
+- **Create / rename / delete combos** — full CRUD from the panel.
+- **Change routing kind** — fallback, round-robin, or fusion.
+- **Search** — filter combos by name or model chain.
+
+## Plugin
+
+| Field   | Value                       |
+| ------- | --------------------------- |
+| ID      | `weinguyen/9router-control` |
+| Widget  | `widget` (bar)              |
+| Panel   | `panel`                     |
+| Service | `service`                   |
+
+Toggle the panel from the bar widget, or with:
+
+```sh
+noctalia msg panel-toggle weinguyen/9router-control:panel
+```
+
+## Requirements
+
+- Noctalia v5.0.0 or higher.
+- A running 9Router instance (dashboard) whose REST API the plugin talks to via
+  `server_host:server_port`.
+- The following external commands, used by the service backend:
+  - `curl` — password login posts to `/api/auth/login` and reads the `Set-Cookie`
+    header (Noctalia's HTTP binding does not expose response headers).
+  - `sha256sum`, `cat`, `cut`, `printf` — compute the CLI authentication token
+    from the `machine-id` and `auth/cli-secret` files when the dashboard has
+    login enabled.
+  - `sleep` — back-off polling while a CLI token computation is in flight.
+
+  Ordinary (login-disabled) usage needs only `curl`; the remaining commands are
+  required when dashboard login is enabled.
+
+## Usage
+
+Click the 9Router widget on the bar to open the panel.
+
+- The **combo list** shows every combo; the search box filters by name or model
+  chain.
+- Select a combo to **reorder** its models (move up/down) and change its routing
+  kind.
+- Use **create / rename / delete** to manage combos without touching the web
+  dashboard.
+
+If the dashboard has login enabled and no CLI token is available, the panel
+shows a login screen where you enter the dashboard password; the plugin then
+reuses the session cookie for subsequent requests.
+
+## Settings
+
+| Setting        | Default      | Description                                                             |
+| -------------- | ------------ | ----------------------------------------------------------------------- |
+| Server Host    | `127.0.0.1`  | Hostname of the 9Router dashboard.                                      |
+| Server Port    | `20128`      | Port of the 9Router dashboard.                                          |
+| Data Directory | `~/.9router` | 9Router data dir, used to compute the CLI token when login is required. |
+| Language       | `auto`       | UI language (auto / English / Tiếng Việt).                              |
+| Debug Logging  | off          | Print debug messages to the Noctalia log.                               |
+
+## Notes
+
+- The plugin talks to the local 9Router REST API (`/api/combos`). By default the
+  dashboard login is disabled, so plain requests work.
+- When login is enabled, the plugin first tries the 9Router CLI token (computed
+  from the `machine-id` and `auth/cli-secret` files, sent as an `x-9r-cli-token`
+  header). If that isn't available, it falls back to a password login and reuses
+  the session cookie.
+- Reordering writes the new `models` array via `PUT /api/combos/:id`.
+
+## Development
+
+- `widget.luau` — bar widget entry.
+- `panel.luau` — chat-style panel surface.
+- `service.luau` — headless API / state backend.
+- `translations/` — user-facing strings.