feat: add private repository support and enhance repository management / 添加私有仓库支持并增强仓库管理功能

[dickiducko]

Summary

1. Private Repository Support

• URL Parser: Implemented repoUrlParser.ts to parse private repository URLs from GitHub, GitLab, Gitea, and other platforms
• Connection Test: Automatically detects the best authentication method (Authorization: token/Bearer, PRIVATE-TOKEN)
• Auth Header Management: Securely stores and uses correct authentication headers for private repository access
• Download Strategy: Supports secure private repository downloads across multiple platforms (GitHub, GitLab, Gitea)

2. Repository Management Enhancement

• Filtering: Added RepoFilter component for filtering repositories by type, name, and other criteria
• Loading Optimization: Implemented useSkillsLoader hook for better loading state management
• UI Improvements: Enhanced repository management panel layout for better user experience
• Internationalization: Completed translations in Chinese, English, and Japanese

Technical Changes

• Extended SkillRepo data structure to support private repository fields
• Refactored download logic to handle public and private repositories separately
• Optimized frontend component architecture for better code reusability

功能概述

1. 私有仓库支持

• URL 解析器：实现 repoUrlParser.ts，支持解析 GitHub/GitLab/Gitea 等平台的私有仓库 URL
• 连通测试：自动探测最佳认证方式（Authorization: token/Bearer、PRIVATE-TOKEN）
• 认证头管理：存储并使用正确的认证头进行私有仓库访问
• 下载策略：支持私有仓库的安全下载，兼容多平台（GitHub、GitLab、Gitea）

2. 仓库管理功能增强

• 筛选功能：新增 RepoFilter 组件，支持按仓库类型、名称等条件进行筛选
• 加载优化：实现 useSkillsLoader hook，提供更完善的加载状态管理
• 界面改进：优化仓库管理面板布局，提升用户体验
• 多语言支持：完善中文、英文、日文三语翻译

技术变更

• 扩展 SkillRepo 数据结构，新增私有仓库相关字段
• 重构下载逻辑，区分处理公共仓库和私有仓库
• 优化前端组件架构，提高代码复用性

[waipanChiu]