Feat/auto failover (#367)

* feat(db): add circuit breaker config table and provider proxy target APIs

Add database support for auto-failover feature:

- Add circuit_breaker_config table for storing failover thresholds
- Add get/update_circuit_breaker_config methods in proxy DAO
- Add reset_provider_health method for manual recovery
- Add set_proxy_target and get_proxy_targets methods in providers DAO
  for managing multi-provider failover configuration

* feat(proxy): implement circuit breaker and provider router for auto-failover

Add core failover logic:

- CircuitBreaker: Tracks provider health with three states:
  - Closed: Normal operation, requests pass through
  - Open: Circuit broken after consecutive failures, skip provider
  - HalfOpen: Testing recovery with limited requests
- ProviderRouter: Routes requests across multiple providers with:
  - Health tracking and automatic failover
  - Configurable failure/success thresholds
  - Auto-disable proxy target after reaching failure threshold
  - Support for manual circuit breaker reset
- Export new types in proxy module

* feat(proxy): add failover Tauri commands and integrate with forwarder

Expose failover functionality to frontend:

- Add Tauri commands: get_proxy_targets, set_proxy_target,
  get_provider_health, reset_circuit_breaker,
  get/update_circuit_breaker_config, get_circuit_breaker_stats
- Register all new commands in lib.rs invoke handler
- Update forwarder with improved error handling and logging
- Integrate ProviderRouter with proxy server startup
- Add provider health tracking in request handlers

* feat(frontend): add failover API layer and TanStack Query hooks

Add frontend data layer for failover management:

- Add failover.ts API: Tauri invoke wrappers for all failover commands
- Add failover.ts query hooks: TanStack Query mutations and queries
  - useProxyTargets, useProviderHealth queries
  - useSetProxyTarget, useResetCircuitBreaker mutations
  - useCircuitBreakerConfig query and mutation
- Update queries.ts with provider health query key
- Update mutations.ts to invalidate health on provider changes
- Add CircuitBreakerConfig and ProviderHealth types

* feat(ui): add auto-failover configuration UI and provider health display

Add comprehensive UI for failover management:

Components:
- ProviderHealthBadge: Display provider health status with color coding
- CircuitBreakerConfigPanel: Configure failure/success thresholds,
  timeout duration, and error rate limits
- AutoFailoverConfigPanel: Manage proxy targets with drag-and-drop
  priority ordering and individual enable/disable controls
- ProxyPanel: Integrate failover tabs for unified proxy management

Provider enhancements:
- ProviderCard: Show health badge and proxy target indicator
- ProviderActions: Add "Set as Proxy Target" action
- EditProviderDialog: Add is_proxy_target toggle
- ProviderList: Support proxy target filtering mode

Other:
- Update App.tsx routing for settings integration
- Update useProviderActions hook with proxy target mutation
- Fix ProviderList tests for updated component API

* fix(usage): stabilize date range to prevent infinite re-renders

* feat(backend): add tool version check command

Add get_tool_versions command to check local and latest versions of
Claude, Codex, and Gemini CLI tools:

- Detect local installed versions via command line execution
- Fetch latest versions from npm registry (Claude, Gemini)
  and GitHub releases API (Codex)
- Return comprehensive version info including error details
  for uninstalled tools
- Register command in Tauri invoke handler

* style(ui): format accordion component code style

Apply consistent code formatting to accordion component:
- Convert double quotes to semicolons at line endings
- Adjust indentation to 2-space standard
- Align with project code style conventions

* refactor(providers): update provider card styling to use theme tokens

Replace hardcoded color classes with semantic design tokens:
- Use bg-card, border-border, text-card-foreground instead of glass-card
- Replace gray/white color literals with muted/foreground tokens
- Change proxy target indicator color from purple to green
- Improve hover states with border-border-active
- Ensure consistent dark mode support via CSS variables

* refactor(proxy): simplify auto-failover config panel structure

Restructure AutoFailoverConfigPanel for better integration:
- Remove internal Card wrapper and expansion toggle (now handled by parent)
- Extract enabled state to props for external control
- Simplify loading state display
- Clean up redundant CardHeader/CardContent wrappers
- ProxyPanel: reduce complexity by delegating to parent components

* feat(settings): enhance settings page with accordion layout and tool versions

Major settings page improvements:

AboutSection:
- Add local tool version detection (Claude, Codex, Gemini)
- Display installed vs latest version comparison with visual indicators
- Show update availability badges and environment check cards

SettingsPage:
- Reorganize advanced settings into collapsible accordion sections
- Add proxy control panel with inline status toggle
- Integrate auto-failover configuration with accordion UI
- Add database and cost calculation config sections

DirectorySettings & WindowSettings:
- Minor styling adjustments for consistency

settings.ts API:
- Add getToolVersions() wrapper for new backend command

* refactor(usage): restructure usage dashboard components

Comprehensive usage statistics panel refactoring:

UsageDashboard:
- Reorganize layout with improved section headers
- Add better loading states and empty state handling

ModelStatsTable & ProviderStatsTable:
- Minor styling updates for consistency

ModelTestConfigPanel & PricingConfigPanel:
- Simplify component structure
- Remove redundant Card wrappers
- Improve form field organization

RequestLogTable:
- Enhance table layout with better column sizing
- Improve pagination controls

UsageSummaryCards:
- Update card styling with semantic tokens
- Better responsive grid layout

UsageTrendChart:
- Refine chart container styling
- Improve legend and tooltip display

* chore(deps): add accordion and animation dependencies

Package updates:
- Add @radix-ui/react-accordion for collapsible sections
- Add cmdk for command palette support
- Add framer-motion for enhanced animations

Tailwind config:
- Add accordion-up/accordion-down animations
- Update darkMode config to support both selector and class
- Reorganize color and keyframe definitions for clarity

* style(app): update header and app switcher styling

App.tsx:
- Replace glass-header with explicit bg-background/80 backdrop-blur
- Update navigation button container to use bg-muted

AppSwitcher:
- Replace hardcoded gray colors with semantic muted/foreground tokens
- Ensure consistent dark mode support via CSS variables
- Add group class for better hover state transitions

src-tauri/src/proxy/provider_router.rs

@@ -0,0 +1,216 @@
+//! 供应商路由器模块
+//!
+//! 负责选择和管理代理目标供应商，实现智能故障转移
+
+use crate::database::Database;
+use crate::error::AppError;
+use crate::provider::Provider;
+use crate::proxy::circuit_breaker::CircuitBreaker;
+use std::collections::HashMap;
+use std::sync::Arc;
+use tokio::sync::RwLock;
+
+/// 供应商路由器
+pub struct ProviderRouter {
+    /// 数据库连接
+    db: Arc<Database>,
+    /// 熔断器管理器 - key 格式: "app_type:provider_id"
+    circuit_breakers: Arc<RwLock<HashMap<String, Arc<CircuitBreaker>>>>,
+}
+
+impl ProviderRouter {
+    /// 创建新的供应商路由器
+    pub fn new(db: Arc<Database>) -> Self {
+        Self {
+            db,
+            circuit_breakers: Arc::new(RwLock::new(HashMap::new())),
+        }
+    }
+
+    /// 选择可用的供应商（支持故障转移）
+    /// 返回按优先级排序的可用供应商列表
+    pub async fn select_providers(&self, app_type: &str) -> Result<Vec<Provider>, AppError> {
+        // 1. 获取所有启用代理的供应商
+        let providers = self.db.get_proxy_targets(app_type).await?;
+
+        if providers.is_empty() {
+            return Err(AppError::Config(
+                "No proxy target providers configured".to_string(),
+            ));
+        }
+
+        log::debug!(
+            "Found {} proxy target providers for app_type: {}",
+            providers.len(),
+            app_type
+        );
+
+        // 2. 按 sort_index 排序（已经在数据库查询中排序了）
+        let sorted_providers: Vec<_> = providers.into_values().collect();
+
+        // 3. 过滤可用的供应商（检查熔断器状态）
+        let mut available_providers = Vec::new();
+
+        for provider in sorted_providers {
+            let circuit_key = format!("{}:{}", app_type, provider.id);
+            let breaker = self.get_or_create_circuit_breaker(&circuit_key).await;
+
+            if breaker.allow_request().await {
+                log::debug!(
+                    "Provider {} is available (circuit state: {:?})",
+                    provider.id,
+                    breaker.get_state().await
+                );
+                available_providers.push(provider);
+            } else {
+                log::warn!(
+                    "Provider {} is unavailable (circuit breaker open)",
+                    provider.id
+                );
+            }
+        }
+
+        if available_providers.is_empty() {
+            return Err(AppError::Config(
+                "All proxy target providers are unavailable (circuit breakers open)".to_string(),
+            ));
+        }
+
+        log::info!(
+            "Selected {} available providers for failover chain",
+            available_providers.len()
+        );
+
+        Ok(available_providers)
+    }
+
+    /// 记录供应商请求结果
+    pub async fn record_result(
+        &self,
+        provider_id: &str,
+        app_type: &str,
+        success: bool,
+        error_msg: Option<String>,
+    ) -> Result<(), AppError> {
+        // 1. 更新熔断器状态
+        let circuit_key = format!("{app_type}:{provider_id}");
+        let breaker = self.get_or_create_circuit_breaker(&circuit_key).await;
+
+        if success {
+            breaker.record_success().await;
+            log::debug!("Provider {provider_id} request succeeded");
+        } else {
+            breaker.record_failure().await;
+            log::warn!(
+                "Provider {} request failed: {}",
+                provider_id,
+                error_msg.as_deref().unwrap_or("Unknown error")
+            );
+        }
+
+        // 2. 更新数据库健康状态
+        self.db
+            .update_provider_health(provider_id, app_type, success, error_msg.clone())
+            .await?;
+
+        // 3. 如果连续失败达到熔断阈值，自动禁用代理目标
+        if !success {
+            let health = self.db.get_provider_health(provider_id, app_type).await?;
+
+            // 获取熔断器配置
+            let config = self.db.get_circuit_breaker_config().await.ok();
+            let failure_threshold = config.map(|c| c.failure_threshold).unwrap_or(5);
+
+            // 如果连续失败达到阈值，自动关闭该供应商的代理开关
+            if health.consecutive_failures >= failure_threshold {
+                log::warn!(
+                    "Provider {} has failed {} times (threshold: {}), auto-disabling proxy target",
+                    provider_id,
+                    health.consecutive_failures,
+                    failure_threshold
+                );
+                self.db
+                    .set_proxy_target(provider_id, app_type, false)
+                    .await?;
+            }
+        }
+
+        Ok(())
+    }
+
+    /// 重置熔断器（手动恢复）
+    #[allow(dead_code)]
+    pub async fn reset_circuit_breaker(&self, circuit_key: &str) {
+        let breakers = self.circuit_breakers.read().await;
+        if let Some(breaker) = breakers.get(circuit_key) {
+            log::info!("Manually resetting circuit breaker for {circuit_key}");
+            breaker.reset().await;
+        }
+    }
+
+    /// 获取熔断器状态
+    #[allow(dead_code)]
+    pub async fn get_circuit_breaker_stats(
+        &self,
+        provider_id: &str,
+        app_type: &str,
+    ) -> Option<crate::proxy::circuit_breaker::CircuitBreakerStats> {
+        let circuit_key = format!("{app_type}:{provider_id}");
+        let breakers = self.circuit_breakers.read().await;
+
+        if let Some(breaker) = breakers.get(&circuit_key) {
+            Some(breaker.get_stats().await)
+        } else {
+            None
+        }
+    }
+
+    /// 获取或创建熔断器
+    async fn get_or_create_circuit_breaker(&self, key: &str) -> Arc<CircuitBreaker> {
+        // 先尝试读锁获取
+        {
+            let breakers = self.circuit_breakers.read().await;
+            if let Some(breaker) = breakers.get(key) {
+                return breaker.clone();
+            }
+        }
+
+        // 如果不存在，获取写锁创建
+        let mut breakers = self.circuit_breakers.write().await;
+
+        // 双重检查，防止竞争条件
+        if let Some(breaker) = breakers.get(key) {
+            return breaker.clone();
+        }
+
+        // 从数据库加载配置
+        let config = self
+            .db
+            .get_circuit_breaker_config()
+            .await
+            .unwrap_or_default();
+
+        log::debug!("Creating new circuit breaker for {key} with config: {config:?}");
+
+        let breaker = Arc::new(CircuitBreaker::new(config));
+        breakers.insert(key.to_string(), breaker.clone());
+
+        breaker
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::database::Database;
+
+    #[tokio::test]
+    async fn test_provider_router_creation() {
+        let db = Arc::new(Database::new_in_memory().unwrap());
+        let router = ProviderRouter::new(db);
+
+        // 测试创建熔断器
+        let breaker = router.get_or_create_circuit_breaker("claude:test").await;
+        assert!(breaker.allow_request().await);
+    }
+}