feat(cli): improve auth dialog UX with clearer three-option layout

- Replace nested API-KEY submenu with flat three-option layout
- Add descriptive labels for each authentication method:
  - Qwen OAuth: Free, up to 1,000 requests/day
  - Alibaba Cloud Coding Plan: Paid, multiple model providers
  - API Key: Bring your own API key
- Simplify region selection for Coding Plan (China vs Global)
- Use DescriptiveRadioButtonSelect for better visual hierarchy
- Add itemGap prop to BaseSelectionList for spacing
- Update i18n strings in en.js, zh.js, and ru.js
- Simplify custom API key configuration info view
- Clean up unused region-specific strings

Closes #2016

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

packages/cli/src/constants/codingPlan.ts

@@ -251,15 +251,9 @@ export function getCodingPlanConfig(region: CodingPlanRegion) {
     region === CodingPlanRegion.CHINA
       ? 'https://coding.dashscope.aliyuncs.com/v1'
       : 'https://coding-intl.dashscope.aliyuncs.com/v1';
-  const regionName =
-    region === CodingPlanRegion.CHINA
-      ? 'Coding Plan (Bailian, China)'
-      : 'Coding Plan (Bailian, Global/Intl)';
-
   return {
     template,
     baseUrl,
-    regionName,
     version: computeCodingPlanVersion(template),
   };
 }