feat: refactor plugin market interaction and migrate to LangBot Space

- Replace plugin detail dialog with hover buttons interaction
- Add "Install" and "View Details" hover buttons on plugin cards
- Remove PluginDetailDialog component
- Update plugin marketplace URL format to /market/{author}/{plugin}
- Redirect all plugin detail views to LangBot Space
- Add i18n support for 4 languages (zh-Hans, en-US, zh-Hant, ja-JP)
- Optimize hover overlay styles for light/dark theme

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

web/src/app/infra/http/CloudServiceClient.ts

@@ -82,6 +82,6 @@ export class CloudServiceClient extends BaseHttpClient {
   }
 
   public getPluginMarketplaceURL(author: string, name: string): string {
-    return `${this.baseURL}/market?author=${author}&plugin=${name}`;
+    return `https://space.langbot.app/market/${author}/${name}`;
   }
 }