feat: Add slashcommand api

docs-site/docs/plugin-development/examples.md

@@ -45,6 +45,61 @@ export function activate(context) {
 
 The action appears as a tile in the server side panel's View plugins menu and runs with `source: 'toolbarAction'`.
 
+## Slash Command Plugin
+
+`toju-plugin.json`
+
+```json
+{
+  "schemaVersion": 1,
+  "id": "example.slash-commands",
+  "title": "Slash Commands",
+  "description": "Registers / commands available from the chat composer.",
+  "version": "1.0.0",
+  "kind": "client",
+  "scope": "client",
+  "apiVersion": "1.0.0",
+  "compatibility": {
+    "minimumTojuVersion": "1.0.0",
+    "verifiedTojuVersion": "1.0.0"
+  },
+  "entrypoint": "./main.js",
+  "capabilities": ["messages.send", "ui.commands"]
+}
+```
+
+`main.js`
+
+```js
+export function activate(context) {
+  const { api } = context;
+
+  // Global: works in chat servers and direct messages.
+  context.subscriptions.push(
+    api.commands.register('shrug', {
+      name: 'shrug',
+      description: 'Append the shrug emoticon',
+      scope: 'global',
+      run: () => api.messages.send('¯\\_(ツ)_/¯')
+    })
+  );
+
+  // Server-scoped: only offered while a chat server is active.
+  context.subscriptions.push(
+    api.commands.register('announce', {
+      name: 'announce',
+      description: 'Post an announcement to the current channel',
+      icon: '📢',
+      scope: 'server',
+      options: [{ name: 'message', type: 'rest', required: true }],
+      run: (slash) => api.messages.send(`📢 ${slash.args.message}`, slash.textChannel?.id)
+    })
+  );
+}
+```
+
+Typing `/` in the composer opens the autocomplete menu. `/shrug` runs immediately; `/announce <message>` fills the composer so the user can type the announcement before sending. See the [Slash Commands API](./api/commands.md) for option parsing and the command context.
+
 ## Settings Page Plugin
 
 ```json