[business-logic] conflict_detect.go unclosed conflict region formats as 'lines N-0'

[topcheer]

File: internal/tool/conflict_detect.go L89-99 + L126-129.

Executed proof: input with '<<<<<<< HEAD' and no closing '>>>>>>>' yields region {StartLine:2, EndLine:0} and warning text 'unresolved merge conflict (lines 2-0) ... HEAD vs (unknown)'. Detection still works but the range is self-contradictory and the unclosed state is not surfaced.

Impact: Low - output clarity.
Fix: render 'line N (unclosed conflict marker)' when EndLine==0.
Verified by independent re-review with executed repro.

[topcheer]

已修复（commit 090ebe2，已合入 main）11 处缺陷：

• [business-logic] desktop_control_windows.go absCoord uses SM_XVIRTUALSCREEN(76) as width - mouse actions broken even single-monitor #818 desktop_control_windows：GetSystemMetrics 索引 76 是虚拟屏原点 X 而非宽度（宽度=78），absCoord 补原点归一化 (x-vsLeft)*65535/vsWidth——Windows 鼠标自动化在所有机器上坐标全错的问题修复
• [business-logic] desktop_control_darwin.go menuSelect generates wrong AppleScript menu chain - menu_select fails on every depth>=2 path #819 desktop_control_darwin：menu_select 子菜单链改用父项命名（System Events 中菜单以其父命名）——depth>=2 的菜单选择不再必然 -1728 报错
• [business-logic] diagnostic_baseline.go formatNewDiagnostics drops Info/Hint severities and misfiles unset(0) as errors #820 diagnostic_baseline：severity 0（LSP 省略）显式归类为 error；Info(3)/Hint(4) 不再静默丢弃（gopls 的 'imported and not used' 正是 Info）——新增 info/hints 渲染段
• [business-logic] edit_match.go lenientRecountRaw double-TrimSpaces all transforms - unique trailing-whitespace edits falsely rejected as ambiguous #821 edit_match：lenientRecountRaw 对 trailing-whitespace-tolerant 变换改用 rstrip-only 语义（保留前导缩进）——唯一正确的编辑不再因缩进不同的第二块被误判为歧义
• [business-logic] create_skill.go duplicate check never consults disk - existing SKILL.md silently overwritten #822 create_skill：写入前 os.Stat 磁盘守卫——CommandMgr 盲区（nil 或加载时跳过的文件）不再导致用户 SKILL.md 被静默覆盖
• [business-logic] commit_analyzer.go Contains-based test-file detection and bare 'ci' substring misclassification #823 commit_analyzer：测试文件判定改 HasSuffix（test_ 前缀全位置匹配）；'ci' 改词边界匹配——latest_report.go/attest_helper.py 不再误归 CatTest
• [business-logic] edit_file.go write-failure path leaks captured diagnostic baseline #824 edit_file：atomicWriteFile 失败路径补 ClearDiagnosticBaseline——磁盘未变时不再残留过期基线
• [business-logic] config_tool.go 'token' substring masking reports max_tokens as 'secret stored securely' #825 config_tool：密钥掩码改白名单（api_key/auth_token/access_token/...）——max_tokens 等数值配置不再显示 '(secret stored securely)'
• [business-logic] diff_scan.go language-blind print( pattern and double-reported binding.pry #826 diff_scan：Python 调试模式（print/pprint）按文件扩展名门控；binding.pry 从 debugStmtPatterns 移除（与 debuggerPatterns 双报）
• [business-logic] conflict_detect.go unclosed conflict region formats as 'lines N-0' #827 conflict_detect：未闭合冲突区域渲染为 'line N (unclosed conflict marker)'，不再出现 'lines 2-0' 自相矛盾
• [business-logic] critical_file.go 'dockerfile.' prefix accepts any extension - dockerfile.py triggers docker-build advice #828 critical_file：dockerfile. 前缀限定已知合法后缀（base/dev/prod/linux/windows/数字版本等）——dockerfile.py/.md 不再触发 docker build 建议

验证：internal/tool 全包测试 ok；GOOS=windows 与 GOOS=darwin 交叉 vet 干净（#818/#819 为平台文件，按 #574 教训必验）。

Co-Authored-By: ggcode noreply@ggcode.dev

[topcheer]

Re-review: incomplete. The unclosed-range rendering was fixed only in the single-region branch (L130-134); the multi-region branch L147-153 still hardcodes 'Lines %d-%d' and renders 'Lines 5-0' for unclosed regions. Apply the same unclosed handling there.