feat: 拆分评审与提交消息提示词并增加 hook 备份与 JSON 输出

- 新增 custom_reviewer_prompt 和 custom_commit_msg_prompt，兼容旧 custom_prompt
- pre-commit hook 安装时备份已有 hook，卸载时恢复
- 支持 --format json 输出评审结果
- diff 发送前自动脱敏敏感信息

internal/reviewer/report.go

@@ -0,0 +1,73 @@
+package reviewer
+
+import (
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+type Finding struct {
+	Severity string `json:"severity"`
+	Location string `json:"location,omitempty"`
+	Message  string `json:"message"`
+}
+
+type ReviewReport struct {
+	Format   string    `json:"format"`
+	Verdict  string    `json:"verdict,omitempty"`
+	Score    int       `json:"score,omitempty"`
+	Findings []Finding `json:"findings"`
+	Raw      string    `json:"raw"`
+}
+
+var (
+	verdictPattern = regexp.MustCompile(`(?mi)(?:结论|verdict)\s*[:：]\s*\[?(PASS|WARN|WARNING|REJECT|BLOCKER|CRITICAL)\]?`)
+	scorePattern   = regexp.MustCompile(`(?mi)(?:评分|score)\s*[:：]\s*(\d{1,3})`)
+	findingPattern = regexp.MustCompile(`(?m)^\s*-\s*\[(BLOCKER|CRITICAL|WARNING|WARN|SUGGESTION|INFO)\]\s+(.+?)\s*$`)
+)
+
+// ParseReviewReport 将模型的 Markdown Review 转成稳定的 JSON 结构。
+// Raw 始终保留完整原文，解析失败时下游仍可自行处理。
+func ParseReviewReport(raw string) ReviewReport {
+	report := ReviewReport{
+		Format:   "git-air-review/v1",
+		Findings: []Finding{},
+		Raw:      strings.TrimSpace(raw),
+	}
+
+	if match := verdictPattern.FindStringSubmatch(raw); len(match) > 1 {
+		report.Verdict = strings.ToUpper(match[1])
+	}
+	if match := scorePattern.FindStringSubmatch(raw); len(match) > 1 {
+		report.Score, _ = strconv.Atoi(match[1])
+		if report.Score > 100 {
+			report.Score = 100
+		}
+	}
+
+	for _, match := range findingPattern.FindAllStringSubmatch(raw, -1) {
+		location, message := splitFindingContent(match[2])
+		report.Findings = append(report.Findings, Finding{
+			Severity: strings.ToUpper(match[1]),
+			Location: location,
+			Message:  message,
+		})
+	}
+	return report
+}
+
+func splitFindingContent(content string) (string, string) {
+	content = strings.TrimSpace(content)
+	parts := strings.SplitN(content, " - ", 2)
+	if len(parts) == 1 {
+		return "", content
+	}
+
+	location := strings.TrimSpace(parts[0])
+	message := strings.TrimSpace(parts[1])
+	// 没有行号/路径特征时，不要误把普通句子当成 location。
+	if !strings.Contains(location, ":") {
+		return "", content
+	}
+	return location, message
+}