feat: 初始化 git-air AI 代码评审 CLI 工具

新增多模型 LLM 客户端、Git diff 提取与过滤、配置管理及 pre-commit 钩子支持。

internal/reviewer/rules.go

@@ -0,0 +1,43 @@
+package reviewer
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// RuleFileCandidates 支持的团队规则文件名优先级列表
+var RuleFileCandidates = []string{
+	".airules",
+	".git-air-rules",
+	".git-air.yaml",
+	".git-air.md",
+}
+
+// LoadCustomRules 读取项目根目录下的团队专属规则
+func LoadCustomRules(repoRoot string) string {
+	if repoRoot == "" {
+		return ""
+	}
+	rulePath := FindRuleFile(repoRoot)
+	if rulePath == "" {
+		return ""
+	}
+	data, err := os.ReadFile(rulePath)
+	if err != nil || len(data) == 0 {
+		return ""
+	}
+	return strings.TrimSpace(string(data))
+}
+
+// FindRuleFile 探测当前仓库根目录下是否存在匹配的规则文件，返回其绝对路径
+func FindRuleFile(repoRoot string) string {
+	for _, filename := range RuleFileCandidates {
+		fullPath := filepath.Join(repoRoot, filename)
+		if info, err := os.Stat(fullPath); err == nil && !info.IsDir() {
+			return fullPath
+		}
+
+	}
+	return ""
+}