Feat/claude skills management (#237)

* feat(skills): add Claude Skills management feature

Implement complete Skills management system with repository discovery,
installation, and lifecycle management capabilities.

Backend:
- Add SkillService with GitHub integration and installation logic
- Implement skill commands (list, install, uninstall, check updates)
- Support multiple skill repositories with caching

Frontend:
- Add Skills management page with repository browser
- Create SkillCard and RepoManager components
- Add badge, card, table UI components
- Integrate Skills API with Tauri commands

Files: 10 files changed, 1488 insertions(+)

* feat(skills): integrate Skills feature into application

Integrate Skills management feature with complete dependency updates,
configuration structure extensions, and internationalization support.

Dependencies:
- Add @radix-ui/react-visually-hidden for accessibility
- Add anyhow, zip, serde_yaml, tempfile for Skills backend
- Enable chrono serde feature for timestamp serialization

Backend Integration:
- Extend MultiAppConfig with SkillStore field
- Implement skills.json migration from legacy location
- Register SkillService and skill commands in main app
- Export skill module in commands and services

Frontend Integration:
- Add Skills page route and dialog in App
- Integrate Skills UI with main navigation

Internationalization:
- Add complete Chinese translations for Skills UI
- Add complete English translations for Skills UI

Code Quality:
- Remove redundant blank lines in gemini_mcp.rs
- Format log statements in mcp.rs

Tests:
- Update import_export_sync tests for SkillStore
- Update mcp_commands tests for new structure

Files: 16 files changed, 540 insertions(+), 39 deletions(-)

* style(skills): improve SkillsPage typography and spacing

Optimize visual hierarchy and readability of Skills page:
- Reduce title size from 2xl to lg with tighter tracking
- Improve description spacing and color contrast
- Enhance empty state with better text hierarchy
- Use explicit gray colors for better dark mode support

* feat(skills): support custom subdirectory path for skill scanning

Add optional skillsPath field to SkillRepo to enable scanning skills
from subdirectories (e.g., "skills/") instead of repository root.

Changes:
- Backend: Add skillsPath field with subdirectory scanning logic
- Frontend: Add skillsPath input field and display in repo list
- Presets: Add cexll/myclaude repo with skills/ subdirectory
- Code quality: Fix clippy warnings (dedup logic, string formatting)

Backward compatible: skillsPath is optional, defaults to root scanning.

* refactor(skills): improve repo manager dialog layout

Optimize dialog structure with fixed header and scrollable content:
- Add flexbox layout with fixed header and scrollable body
- Remove outer border wrapper for cleaner appearance
- Match SkillsPage design pattern for consistency
- Improve UX with better content hierarchy

src-tauri/src/commands/skill.rs

@@ -0,0 +1,163 @@
+use crate::services::skill::SkillState;
+use crate::services::{Skill, SkillRepo, SkillService};
+use crate::store::AppState;
+use chrono::Utc;
+use std::sync::Arc;
+use tauri::State;
+
+pub struct SkillServiceState(pub Arc<SkillService>);
+
+#[tauri::command]
+pub async fn get_skills(
+    service: State<'_, SkillServiceState>,
+    app_state: State<'_, AppState>,
+) -> Result<Vec<Skill>, String> {
+    let repos = {
+        let config = app_state.config.read().map_err(|e| e.to_string())?;
+        config.skills.repos.clone()
+    };
+
+    service
+        .0
+        .list_skills(repos)
+        .await
+        .map_err(|e| e.to_string())
+}
+
+#[tauri::command]
+pub async fn install_skill(
+    directory: String,
+    service: State<'_, SkillServiceState>,
+    app_state: State<'_, AppState>,
+) -> Result<bool, String> {
+    // 先在不持有写锁的情况下收集仓库与技能信息
+    let repos = {
+        let config = app_state.config.read().map_err(|e| e.to_string())?;
+        config.skills.repos.clone()
+    };
+
+    let skills = service
+        .0
+        .list_skills(repos)
+        .await
+        .map_err(|e| e.to_string())?;
+
+    let skill = skills
+        .iter()
+        .find(|s| s.directory.eq_ignore_ascii_case(&directory))
+        .ok_or_else(|| "技能不存在".to_string())?;
+
+    if !skill.installed {
+        let repo = SkillRepo {
+            owner: skill
+                .repo_owner
+                .clone()
+                .ok_or_else(|| "缺少仓库信息".to_string())?,
+            name: skill
+                .repo_name
+                .clone()
+                .ok_or_else(|| "缺少仓库信息".to_string())?,
+            branch: skill
+                .repo_branch
+                .clone()
+                .unwrap_or_else(|| "main".to_string()),
+            enabled: true,
+            skills_path: None, // 安装时使用默认路径
+        };
+
+        service
+            .0
+            .install_skill(directory.clone(), repo)
+            .await
+            .map_err(|e| e.to_string())?;
+    }
+
+    {
+        let mut config = app_state.config.write().map_err(|e| e.to_string())?;
+
+        config.skills.skills.insert(
+            directory.clone(),
+            SkillState {
+                installed: true,
+                installed_at: Utc::now(),
+            },
+        );
+    }
+
+    app_state.save().map_err(|e| e.to_string())?;
+
+    Ok(true)
+}
+
+#[tauri::command]
+pub fn uninstall_skill(
+    directory: String,
+    service: State<'_, SkillServiceState>,
+    app_state: State<'_, AppState>,
+) -> Result<bool, String> {
+    service
+        .0
+        .uninstall_skill(directory.clone())
+        .map_err(|e| e.to_string())?;
+
+    {
+        let mut config = app_state.config.write().map_err(|e| e.to_string())?;
+
+        config.skills.skills.remove(&directory);
+    }
+
+    app_state.save().map_err(|e| e.to_string())?;
+
+    Ok(true)
+}
+
+#[tauri::command]
+pub fn get_skill_repos(
+    _service: State<'_, SkillServiceState>,
+    app_state: State<'_, AppState>,
+) -> Result<Vec<SkillRepo>, String> {
+    let config = app_state.config.read().map_err(|e| e.to_string())?;
+
+    Ok(config.skills.repos.clone())
+}
+
+#[tauri::command]
+pub fn add_skill_repo(
+    repo: SkillRepo,
+    service: State<'_, SkillServiceState>,
+    app_state: State<'_, AppState>,
+) -> Result<bool, String> {
+    {
+        let mut config = app_state.config.write().map_err(|e| e.to_string())?;
+
+        service
+            .0
+            .add_repo(&mut config.skills, repo)
+            .map_err(|e| e.to_string())?;
+    }
+
+    app_state.save().map_err(|e| e.to_string())?;
+
+    Ok(true)
+}
+
+#[tauri::command]
+pub fn remove_skill_repo(
+    owner: String,
+    name: String,
+    service: State<'_, SkillServiceState>,
+    app_state: State<'_, AppState>,
+) -> Result<bool, String> {
+    {
+        let mut config = app_state.config.write().map_err(|e| e.to_string())?;
+
+        service
+            .0
+            .remove_repo(&mut config.skills, owner, name)
+            .map_err(|e| e.to_string())?;
+    }
+
+    app_state.save().map_err(|e| e.to_string())?;
+
+    Ok(true)
+}