test(channels): add comprehensive test suites for channel adapters

- Add ChannelBase, GroupGate, SenderGate, SessionRouter tests
- Add DingTalk markdown utility tests
- Add Weixin media and send helper tests
- Add CLI channel config-utils and pidfile tests
- Configure vitest for all channel packages
- Exclude test files from TypeScript build

Tests cover attachment handling, block streaming, gating policies,
session routing, markdown conversion, config parsing, and service management.

Co-authored-by: Qwen-Coder <qwen-coder@alibabacloud.com>

vitest.config.ts

@@ -7,6 +7,10 @@ export default defineConfig({
       'packages/core',
       'packages/vscode-ide-companion',
       'packages/sdk-typescript',
+      'packages/channels/base',
+      'packages/channels/dingtalk',
+      'packages/channels/telegram',
+      'packages/channels/weixin',
       'integration-tests',
       'scripts',
     ],