feat: support per-bot workspace switching

plugin-src/host/channels/shared/workspace-rpc.mjs

@@ -0,0 +1,25 @@
+import { isAbsolute } from 'node:path';
+
+export const SET_WORKSPACE_ENDPOINT = 'bot.workspace.set';
+
+export function validWorkspacePayload(payload) {
+  return payload !== null
+    && typeof payload === 'object'
+    && !Array.isArray(payload)
+    && Object.keys(payload).every((key) => ['botId', 'workspace'].includes(key))
+    && typeof payload.botId === 'string'
+    && /^[A-Za-z0-9_-]{1,128}$/.test(payload.botId)
+    && typeof payload.workspace === 'string'
+    && payload.workspace.length <= 4_096
+    && isAbsolute(payload.workspace.trim());
+}
+
+export function publicWorkspaceError(error) {
+  if (![
+    'workspace-not-absolute',
+    'workspace-not-found',
+    'workspace-not-directory',
+    'workspace-bot-not-found',
+  ].includes(error?.code)) return null;
+  return { code: error.code, message: error.message };
+}