feat: Kiro API Proxy - OpenAI/Anthropic compatible API service

- Multi-account pool with round-robin load balancing
- Auto token refresh for IAM IdC and Social auth
- Streaming support (SSE)
- Web admin panel with account management
- Docker support with GitHub Actions CI/CD
- Machine ID management per account
- Usage tracking (requests, tokens, credits)

pool/account.go

@@ -0,0 +1,189 @@
+// Package pool 账号池管理
+// 实现轮询负载均衡、错误冷却、Token 刷新
+package pool
+
+import (
+	"kiro-api-proxy/config"
+	"sync"
+	"sync/atomic"
+	"time"
+)
+
+// AccountPool 账号池
+type AccountPool struct {
+	mu           sync.RWMutex
+	accounts     []config.Account
+	currentIndex uint64
+	cooldowns    map[string]time.Time // 账号冷却时间
+	errorCounts  map[string]int       // 连续错误计数
+}
+
+var (
+	pool     *AccountPool
+	poolOnce sync.Once
+)
+
+// GetPool 获取全局账号池单例
+func GetPool() *AccountPool {
+	poolOnce.Do(func() {
+		pool = &AccountPool{
+			cooldowns:   make(map[string]time.Time),
+			errorCounts: make(map[string]int),
+		}
+		pool.Reload()
+	})
+	return pool
+}
+
+// Reload 从配置重新加载账号
+func (p *AccountPool) Reload() {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	p.accounts = config.GetEnabledAccounts()
+}
+
+// GetNext 获取下一个可用账号（轮询）
+func (p *AccountPool) GetNext() *config.Account {
+	p.mu.RLock()
+	defer p.mu.RUnlock()
+
+	if len(p.accounts) == 0 {
+		return nil
+	}
+
+	now := time.Now()
+	n := len(p.accounts)
+
+	// 轮询查找可用账号
+	for i := 0; i < n; i++ {
+		idx := atomic.AddUint64(&p.currentIndex, 1) % uint64(n)
+		acc := &p.accounts[idx]
+
+		// 跳过冷却中的账号
+		if cooldown, ok := p.cooldowns[acc.ID]; ok && now.Before(cooldown) {
+			continue
+		}
+
+		// 跳过即将过期的 Token
+		if acc.ExpiresAt > 0 && time.Now().Unix() > acc.ExpiresAt-300 {
+			continue
+		}
+
+		return acc
+	}
+
+	// 无可用账号，返回冷却时间最短的
+	var best *config.Account
+	var earliest time.Time
+	for i := range p.accounts {
+		acc := &p.accounts[i]
+		if cooldown, ok := p.cooldowns[acc.ID]; ok {
+			if best == nil || cooldown.Before(earliest) {
+				best = acc
+				earliest = cooldown
+			}
+		} else {
+			return acc
+		}
+	}
+	return best
+}
+
+// GetByID 根据 ID 获取账号
+func (p *AccountPool) GetByID(id string) *config.Account {
+	p.mu.RLock()
+	defer p.mu.RUnlock()
+	for i := range p.accounts {
+		if p.accounts[i].ID == id {
+			return &p.accounts[i]
+		}
+	}
+	return nil
+}
+
+// RecordSuccess 记录请求成功，清除冷却
+func (p *AccountPool) RecordSuccess(id string) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	delete(p.cooldowns, id)
+	p.errorCounts[id] = 0
+}
+
+// RecordError 记录请求错误，设置冷却
+func (p *AccountPool) RecordError(id string, isQuotaError bool) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+
+	p.errorCounts[id]++
+
+	if isQuotaError {
+		// 配额错误，冷却 1 小时
+		p.cooldowns[id] = time.Now().Add(time.Hour)
+	} else if p.errorCounts[id] >= 3 {
+		// 连续 3 次错误，冷却 1 分钟
+		p.cooldowns[id] = time.Now().Add(time.Minute)
+	}
+}
+
+// UpdateToken 更新账号 Token
+func (p *AccountPool) UpdateToken(id, accessToken, refreshToken string, expiresAt int64) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	for i := range p.accounts {
+		if p.accounts[i].ID == id {
+			p.accounts[i].AccessToken = accessToken
+			if refreshToken != "" {
+				p.accounts[i].RefreshToken = refreshToken
+			}
+			p.accounts[i].ExpiresAt = expiresAt
+			break
+		}
+	}
+}
+
+// Count 返回账号总数
+func (p *AccountPool) Count() int {
+	p.mu.RLock()
+	defer p.mu.RUnlock()
+	return len(p.accounts)
+}
+
+// AvailableCount 返回可用账号数
+func (p *AccountPool) AvailableCount() int {
+	p.mu.RLock()
+	defer p.mu.RUnlock()
+	now := time.Now()
+	count := 0
+	for _, acc := range p.accounts {
+		if cooldown, ok := p.cooldowns[acc.ID]; ok && now.Before(cooldown) {
+			continue
+		}
+		count++
+	}
+	return count
+}
+
+// UpdateStats 更新账号统计
+func (p *AccountPool) UpdateStats(id string, tokens int, credits float64) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	for i := range p.accounts {
+		if p.accounts[i].ID == id {
+			p.accounts[i].RequestCount++
+			p.accounts[i].TotalTokens += tokens
+			p.accounts[i].TotalCredits += credits
+			p.accounts[i].LastUsed = time.Now().Unix()
+			go config.UpdateAccountStats(id, p.accounts[i].RequestCount, p.accounts[i].ErrorCount, p.accounts[i].TotalTokens, p.accounts[i].TotalCredits, p.accounts[i].LastUsed)
+			break
+		}
+	}
+}
+
+// GetAllAccounts 获取所有账号副本
+func (p *AccountPool) GetAllAccounts() []config.Account {
+	p.mu.RLock()
+	defer p.mu.RUnlock()
+	result := make([]config.Account, len(p.accounts))
+	copy(result, p.accounts)
+	return result
+}