feat: 提交详情能看 diff，也能丢给 AI 审这一次改动。文件检查可单独排除路径，TODO 只认大写，避免把 todo 表和模块当成待办标记。

热力图按容器宽度铺满一年，不再横向滚动。托盘右键换成可换皮肤的弹层；更新下载显示进度，退出后再由脚本拉起安装器，避免还占着 exe。

service/git.go

@@ -3,6 +3,7 @@ package service
 import (
 	"context"
 	"errors"
+	"fmt"
 	"os/exec"
 	"sort"
 	"strconv"
@@ -259,9 +260,181 @@ func (g GitService) CommitDetail(ctx context.Context, dir, hash string) (model.G
 		d.Added += a
 		d.Deleted += del
 	}
+	if patch, e := g.run(ctx, dir, "show", "--format=", "--patch", "--no-color", "--unified=3", hash); e == nil {
+		attachCommitPatches(&d, patch)
+	}
 	return d, nil
 }
 
+const (
+	maxPatchLines      = 500
+	maxPatchBytes      = 80_000
+	maxPatchBytesTotal = 400_000
+)
+
+type parsedPatch struct {
+	Path      string
+	Text      string
+	Binary    bool
+	Truncated bool
+}
+
+func attachCommitPatches(d *model.GitCommitDetail, raw string) {
+	patches := parseCommitPatches(raw)
+	used := 0
+	for i := range d.Files {
+		key := patchFileKey(d.Files[i].Path)
+		p, ok := patches[key]
+		if !ok {
+			p, ok = patches[d.Files[i].Path]
+		}
+		if !ok {
+			continue
+		}
+		d.Files[i].Binary = p.Binary
+		if p.Binary {
+			continue
+		}
+		if used+len(p.Text) > maxPatchBytesTotal {
+			d.Files[i].Truncated = true
+			continue
+		}
+		d.Files[i].Patch = p.Text
+		d.Files[i].Truncated = p.Truncated
+		used += len(p.Text)
+	}
+}
+
+func patchFileKey(path string) string {
+	if i := strings.LastIndex(path, " => "); i >= 0 {
+		return strings.Trim(path[i+4:], "{}")
+	}
+	return path
+}
+
+func parseCommitPatches(raw string) map[string]parsedPatch {
+	out := map[string]parsedPatch{}
+	raw = strings.ReplaceAll(strings.TrimSpace(raw), "\r\n", "\n")
+	if raw == "" {
+		return out
+	}
+	parts := strings.Split(raw, "\ndiff --git ")
+	for i, part := range parts {
+		if i == 0 {
+			if !strings.HasPrefix(part, "diff --git ") {
+				continue
+			}
+		} else {
+			part = "diff --git " + part
+		}
+		p := parseOneDiff(part)
+		if p.Path == "" {
+			continue
+		}
+		out[p.Path] = p
+	}
+	return out
+}
+
+func parseOneDiff(block string) parsedPatch {
+	p := parsedPatch{Path: diffPath(block)}
+	if strings.Contains(block, "Binary files ") || strings.Contains(block, "GIT binary patch") {
+		p.Binary = true
+		return p
+	}
+	lines := strings.Split(block, "\n")
+	kept := make([]string, 0, len(lines))
+	for _, line := range lines {
+		if strings.HasPrefix(line, "diff --git ") || strings.HasPrefix(line, "index ") || strings.HasPrefix(line, "new file mode ") || strings.HasPrefix(line, "deleted file mode ") || strings.HasPrefix(line, "similarity index ") || strings.HasPrefix(line, "rename ") || strings.HasPrefix(line, "copy ") {
+			continue
+		}
+		kept = append(kept, line)
+	}
+	text := strings.Join(kept, "\n")
+	if n := strings.Count(text, "\n") + 1; n > maxPatchLines {
+		kept = strings.Split(text, "\n")[:maxPatchLines]
+		text = strings.Join(kept, "\n")
+		p.Truncated = true
+	}
+	if len(text) > maxPatchBytes {
+		text = text[:maxPatchBytes]
+		p.Truncated = true
+	}
+	p.Text = strings.TrimRight(text, "\n")
+	return p
+}
+
+func diffPath(block string) string {
+	for _, line := range strings.Split(block, "\n") {
+		if strings.HasPrefix(line, "+++ b/") {
+			return strings.TrimPrefix(line, "+++ b/")
+		}
+		if strings.HasPrefix(line, "+++ /dev/null") {
+			continue
+		}
+		if strings.HasPrefix(line, "--- a/") {
+			fallback := strings.TrimPrefix(line, "--- a/")
+			if fallback != "/dev/null" {
+				// 删除文件没有 +++ b/，用旧路径
+				if !strings.Contains(block, "+++ b/") {
+					return fallback
+				}
+			}
+		}
+	}
+	first, _, _ := strings.Cut(block, "\n")
+	rest := strings.TrimPrefix(first, "diff --git ")
+	if i := strings.LastIndex(rest, " b/"); i >= 0 {
+		return strings.Trim(rest[i+3:], `"`)
+	}
+	return ""
+}
+
+const aiDiffMaxBytes = 80_000
+
+// FormatCommitDiffForAI 把提交明细收成给模型看的文本，超长时省略部分文件 patch。
+func FormatCommitDiffForAI(d model.GitCommitDetail, maxBytes int) string {
+	if maxBytes <= 0 {
+		maxBytes = aiDiffMaxBytes
+	}
+	var b strings.Builder
+	fmt.Fprintf(&b, "## 本次提交\n- 哈希: %s\n- 作者: %s <%s>\n- 时间: %s\n- 说明: %s\n- 变更: +%d / -%d，共 %d 个文件\n",
+		d.Hash, d.Author, d.Email, d.Date, d.Message, d.Added, d.Deleted, len(d.Files))
+	b.WriteString("\n## 变更文件\n")
+	for i, f := range d.Files {
+		if i >= 80 {
+			fmt.Fprintf(&b, "- … 其余 %d 个文件已省略\n", len(d.Files)-i)
+			break
+		}
+		note := ""
+		if f.Binary {
+			note = " [binary]"
+		} else if f.Truncated {
+			note = " [truncated]"
+		}
+		fmt.Fprintf(&b, "- %s %s +%d/-%d%s\n", f.Status, f.Path, f.Added, f.Deleted, note)
+	}
+	b.WriteString("\n## Diff\n")
+	used := 0
+	omitted := 0
+	for _, f := range d.Files {
+		if f.Binary || f.Patch == "" {
+			continue
+		}
+		block := fmt.Sprintf("### %s\n```diff\n%s\n```\n", f.Path, f.Patch)
+		if used+len(block) > maxBytes {
+			omitted++
+			continue
+		}
+		b.WriteString(block)
+		used += len(block)
+	}
+	if omitted > 0 {
+		fmt.Fprintf(&b, "\n（另有 %d 个文件的 diff 因过长未纳入）\n", omitted)
+	}
+	return b.String()
+}
+
 // CheckoutBranch 在修改工作区前先检查已跟踪和未跟踪变更；发现任何内容都拒绝切换。
 func (g GitService) CheckoutBranch(ctx context.Context, dir, ref string) (model.CheckoutResult, error) {
 	dirty, e := g.run(ctx, dir, "status", "--porcelain")