fix: skip LFS smudge during workspace clone

[lishuceo]

Summary

• 含 Git LFS 的仓库（如 UrhoX）在创建工作区时 clone 失败，因为 bare cache 不含 LFS 对象，本地 clone 时 smudge filter 无法下载大文件
• 在 execFileSync 的 clone 环境变量中添加 GIT_LFS_SKIP_SMUDGE=1，跳过 LFS 文件下载
• Claude 只需要源码不需要二进制资产，跳过不影响功能；如需要可后续 git lfs pull 按需拉取

Test plan

• 新增单元测试验证 clone 环境变量包含 GIT_LFS_SKIP_SMUDGE=1
• 全部 31 个 manager 测试通过
• 手动验证 UrhoX 仓库 clone 成功（GIT_LFS_SKIP_SMUDGE=1 git clone ...）

🤖 Generated with Claude Code

[claude]

Claude finished @lishuceo's task in 49s —— View job

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PR Review: fix: skip LFS smudge during workspace clone

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✅ Approved — Clean, well-scoped fix.

What it does: Adds GIT_LFS_SKIP_SMUDGE=1 to the environment of the local git clone in manager.ts:155-158, preventing LFS smudge filter failures when cloning from the bare cache (which doesn't contain LFS objects).

Review notes:

• Correct scope: The fix is only applied to the local clone in manager.ts, not to the bare clone in cache.ts. This is correct — bare clones (--bare) don't check out files, so LFS smudge doesn't run there.
• ...process.env spread: Properly inherits the full parent environment, only overriding the single LFS variable. No risk of breaking other git operations.
• Test coverage: New test verifies the env is set on the execFileSync call. Straightforward and sufficient.
• No issues found with confidence ≥ 75.

Minimal, targeted fix with appropriate test coverage. LGTM.