Fix various Windows related path issues

[jimpark]

While trying this tool on my Windows 11, I found many issues with the paths, including where to find VS Code & Zed settings, mixed forward and backslashes, HOME vs USERPROFILE, etc.

[DeusData]

Thanks @jimpark for tackling the Windows path issues — we appreciate you testing on Windows 11 and identifying the problems.

Unfortunately we can't merge this PR in its current form:

• The diff is +12,719/-12,473 lines across 9 core files, making security review impractical. Our CONTRIBUTING.md requires PRs to be focused and reviewable.
• The branch is based on an older version of main and conflicts with 4 files we've heavily modified since (cli.c, mcp.c, pipeline.c, store.c).
• The first commit accidentally included .claude/settings.local.json.

We're merging PR #88 by @bingh0 which addresses the core issue (HOME → USERPROFILE fallback) in a focused +64/-43 change.

If you have additional Windows-specific fixes beyond HOME/USERPROFILE (mixed forward/backslashes, VS Code/Zed settings paths), we'd welcome those as a separate, focused PR based on current main — one fix per PR as per our contributing guidelines. The path separator normalization in particular would be valuable.

[DeusData]

Follow-up: we've merged PR #88 which fixes the HOME vs USERPROFILE issue (the core install blocker on Windows).

For the remaining Windows issues you mentioned (mixed slashes, VS Code/Zed config paths), could you open individual issues with specific reproduction steps? For example:

• Which file/function produces the wrong path?
• What does the path look like vs what it should be?
• Which Windows version + shell (cmd, PowerShell, MSYS2)?

We'd be happy to fix them as focused PRs. One issue per problem makes it easier to track and test.