feat(i18n): add English support for host-side chat messages

Wrap all user-facing chat text in src/channels with a host-side t()
translator (Chinese is the identity default, so untranslated text is
always sent verbatim in Chinese). English is selected via the host
plugin config `language: en` or the DSH_IM_LANGUAGE environment
variable, and the settings UI keeps following the DSH web locale.

- add src/channels/shared/i18n.mjs with setImHostLanguage/t() and a
  Chinese-key -> English dictionary split by area (shared + channels)
- complete the English dictionary for every t() key in src/channels,
  including the feishu channel (welcome/help, repair flow, interactive
  cards, watch flow) and the shared command/approval/stream text
- wrap previously untranslated chat-facing strings in feishu bridge,
  feishu runtime, editable-message-stream, harness-client,
  connection-test and image-prompt
- dedupe dictionary entries that existed in multiple channel files and
  canonicalize conflicting translations into the shared dictionaries
- extend the i18n unit test to decode string-literal escapes so keys
  containing \n are checked correctly
- document the language switch in README.md, README.en.md and
  CHANGELOG.md, and rebuild lib/index.js

Added English support for bot chat messages across all nine IM
channels and AI Office without changing any Chinese output.

src/channels/whatsapp/config-store.mjs

@@ -2,6 +2,8 @@ import { createHash } from 'node:crypto';
 import { mkdir, readFile, rename, unlink, writeFile } from 'node:fs/promises';
 import { dirname } from 'node:path';
 
+import { t } from '../shared/i18n.mjs';
+
 const EMPTY_DOCUMENT = Object.freeze({ version: 2, bots: Object.freeze([]) });
 const BOT_ID_PATTERN = /^whatsapp_[a-f0-9]{24}$/;
 const AUTH_DIRECTORY_PATTERN = /^[a-f0-9-]{36}$/;
@@ -30,7 +32,7 @@ export function deriveWhatsappBotId(accountJid) {
 
 export function maskWhatsappAccount(accountJid) {
   const digits = normalizeWhatsappAccountJid(accountJid)?.split('@')[0] ?? '';
-  if (!digits) return 'WhatsApp账号';
+  if (!digits) return t('WhatsApp账号');
   if (digits.length <= 7) return `${digits.slice(0, 2)}•••${digits.slice(-2)}`;
   return `${digits.slice(0, 4)}••••${digits.slice(-4)}`;
 }

src/channels/whatsapp/whatsapp-bridge.mjs

@@ -1,9 +1,11 @@
+import { t } from '../shared/i18n.mjs';
 import { createTextBridgeStatus, TextHarnessBridge } from '../shared/text-harness-bridge.mjs';
 
 export const WHATSAPP_DESCRIPTOR = Object.freeze({
   key: 'whatsapp',
   label: 'WhatsApp',
-  connectionLabel: ' Web 关联设备',
+  // Translated lazily: t() must run after setImHostLanguage, not at import time.
+  get connectionLabel() { return t(' Web 关联设备'); },
 });
 
 export class WhatsappHarnessBridge extends TextHarnessBridge {

src/channels/whatsapp/whatsapp-controller.mjs

@@ -1,6 +1,7 @@
 import { randomUUID } from 'node:crypto';
 
 import { connectionTestMessage } from '../shared/connection-test.mjs';
+import { t } from '../shared/i18n.mjs';
 import {
   deriveWhatsappBotId,
   maskWhatsappAccount,
@@ -83,8 +84,8 @@ export class WhatsappController {
           this.#errors.set(config.botId, safeError(
             error?.code === 'relink-required' ? 'relink-required' : 'connection-failed',
             error?.code === 'relink-required'
-              ? 'WhatsApp 关联设备已失效，请移除后重新扫码。'
-              : 'WhatsApp 连接未就绪，插件会自动重试。',
+              ? t('WhatsApp 关联设备已失效，请移除后重新扫码。')
+              : t('WhatsApp 连接未就绪，插件会自动重试。'),
           ));
           this.#logger.warn?.(`[dsh-im:whatsapp] bot ${config.botId} failed to initialize`);
         } finally {
@@ -172,7 +173,7 @@ export class WhatsappController {
       await record.task?.catch(() => undefined);
       if (!TERMINAL_ATTEMPT_STATES.has(record.state)) {
         record.state = 'cancelled';
-        record.error = safeError('cancelled', '扫码接入已取消。');
+        record.error = safeError('cancelled', t('扫码接入已取消。'));
       }
       await this.#deleteAuth(record.authDirectory).catch(() => undefined);
     }
@@ -192,8 +193,8 @@ export class WhatsappController {
         this.#errors.set(botId, safeError(
           error?.code === 'relink-required' ? 'relink-required' : 'connection-failed',
           error?.code === 'relink-required'
-            ? 'WhatsApp 关联设备已失效，请移除后重新扫码。'
-            : 'WhatsApp 连接仍未就绪，请稍后重试。',
+            ? t('WhatsApp 关联设备已失效，请移除后重新扫码。')
+            : t('WhatsApp 连接仍未就绪，请稍后重试。'),
         ));
         throw error;
       } finally {
@@ -209,14 +210,14 @@ export class WhatsappController {
     return this.#withBotTransition(botId, async () => {
       const runtime = this.#runtimes.get(botId);
       if (!runtime?.status?.ready || typeof runtime.sendConnectionTest !== 'function') {
-        const error = new Error('WhatsApp机器人尚未连接');
+        const error = new Error(t('WhatsApp机器人尚未连接'));
         error.code = 'test-target-unavailable';
         throw error;
       }
       return runtime.sendConnectionTest(
         connectionTestMessage(
           `${config.name}（${maskWhatsappAccount(config.accountJid)}）`,
-          'WhatsApp机器人',
+          t('WhatsApp机器人'),
         ),
       );
     });
@@ -275,8 +276,8 @@ export class WhatsappController {
         bot: { name: config.name, idMasked: maskWhatsappAccount(config.accountJid) },
         health: {
           status: connected ? 'healthy' : state === 'error' ? 'error' : 'offline',
-          summary: connected ? 'WhatsApp Web 关联设备运行正常'
-            : state === 'error' ? 'WhatsApp 连接未就绪' : 'WhatsApp 连接当前离线',
+          summary: connected ? t('WhatsApp Web 关联设备运行正常')
+            : state === 'error' ? t('WhatsApp 连接未就绪') : t('WhatsApp 连接当前离线'),
           lastCheckedAt: runtimeStatus?.lastCheckedAt ?? null,
           lastConnectedAt: runtimeStatus?.lastConnectedAt ?? null,
         },
@@ -340,7 +341,7 @@ export class WhatsappController {
         await this.#startRuntime(config);
         this.#errors.delete(botId);
       } catch (error) {
-        this.#errors.set(botId, safeError('connection-failed', 'WhatsApp 已绑定，消息连接暂未就绪。'));
+        this.#errors.set(botId, safeError('connection-failed', t('WhatsApp 已绑定，消息连接暂未就绪。')));
         this.#logger.warn?.(`[dsh-im:whatsapp] bot ${botId} did not reconnect after QR binding`);
       }
       if (previous?.authDirectory && previous.authDirectory !== config.authDirectory) {
@@ -363,11 +364,11 @@ export class WhatsappController {
         await this.#deleteAuth(record.authDirectory).catch(() => undefined);
         if (previous) await this.#startRuntime(previous).catch(() => undefined);
         record.state = 'cancelled';
-        record.error = safeError('cancelled', '扫码接入已取消。');
+        record.error = safeError('cancelled', t('扫码接入已取消。'));
       } else {
         await this.#deleteAuth(record.authDirectory).catch(() => undefined);
         record.state = 'failed';
-        record.error = safeError('activation-failed', 'WhatsApp 已扫码，但无法保存关联设备。');
+        record.error = safeError('activation-failed', t('WhatsApp 已扫码，但无法保存关联设备。'));
         this.#logger.error?.('[dsh-im:whatsapp] unable to persist linked-device session');
       }
     } finally {
@@ -380,10 +381,10 @@ export class WhatsappController {
     if (TERMINAL_ATTEMPT_STATES.has(record.state)) return;
     if (record.controller.signal.aborted || error?.name === 'AbortError') {
       record.state = 'cancelled';
-      record.error = safeError('cancelled', '扫码接入已取消。');
+      record.error = safeError('cancelled', t('扫码接入已取消。'));
     } else {
       record.state = 'failed';
-      record.error = safeError('qr-connect-failed', '无法连接 WhatsApp，请重新生成二维码。');
+      record.error = safeError('qr-connect-failed', t('无法连接 WhatsApp，请重新生成二维码。'));
     }
     if (this.#activeAttemptId === record.id) this.#activeAttemptId = null;
     await record.session?.close().catch(() => undefined);

src/channels/whatsapp/whatsapp-runtime.mjs

@@ -7,6 +7,7 @@ import {
 } from '@whiskeysockets/baileys';
 
 import { splitMessageText } from '../shared/editable-message-stream.mjs';
+import { t } from '../shared/i18n.mjs';
 import { ImagePromptError } from '../shared/image-prompt.mjs';
 import { trackOutboundArtifactProviderPromise } from '../shared/semantic/artifact.mjs';
 import { createWhatsappBridgeStatus, WhatsappHarnessBridge } from './whatsapp-bridge.mjs';
@@ -107,7 +108,7 @@ async function downloadWhatsappImage(message, download, {
       throw new ImagePromptError(
         'image-download-failed',
         `WhatsApp image download timed out after ${IMAGE_DOWNLOAD_TIMEOUT_MS} ms`,
-        '图片下载失败，请重新发送后再试。',
+        t('图片下载失败，请重新发送后再试。'),
       );
     }
     throw error;
@@ -126,7 +127,7 @@ async function downloadWhatsappImage(message, download, {
         throw new ImagePromptError(
           'image-too-large',
           `WhatsApp image exceeded ${maxBytes} bytes`,
-          '图片超过 5 MB，请压缩后重试。',
+          t('图片超过 5 MB，请压缩后重试。'),
         );
       }
       chunks.push(data);
@@ -137,7 +138,7 @@ async function downloadWhatsappImage(message, download, {
       throw new ImagePromptError(
         'image-download-failed',
         `WhatsApp image stream timed out after ${IMAGE_DOWNLOAD_TIMEOUT_MS} ms`,
-        '图片下载失败，请重新发送后再试。',
+        t('图片下载失败，请重新发送后再试。'),
       );
     }
     throw error;
@@ -640,7 +641,7 @@ export class WhatsappRuntime {
 
   async sendConnectionTest(text) {
     if (!this.#status.ready || !this.#client) {
-      const error = new Error('WhatsApp机器人尚未连接');
+      const error = new Error(t('WhatsApp机器人尚未连接'));
       error.code = 'test-target-unavailable';
       throw error;
     }

src/channels/whatsapp/whatsapp-web-session.mjs

@@ -7,6 +7,8 @@ import makeWASocket, {
   useMultiFileAuthState,
 } from '@whiskeysockets/baileys';
 
+import { t } from '../shared/i18n.mjs';
+
 const SILENT_LOGGER = Object.freeze({
   level: 'silent',
   trace() {},
@@ -57,7 +59,7 @@ function normalizeIdentity(socket, authState) {
   return {
     accountJid,
     name: typeof source?.name === 'string' && source.name.trim()
-      ? source.name.trim().slice(0, 100) : 'WhatsApp机器人',
+      ? source.name.trim().slice(0, 100) : t('WhatsApp机器人'),
   };
 }