Layout step fails on Windows with error "Failed to find a parent section match for a page"

[Atomk]

Zig's website builds fail on Windows with error "Failed to find a parent section match for a page" because some path separators are hardcoded to /, and cached paths are saved with the native separator resulting in failing equality checks with paths using the / separator.

md_rel_path = 'news/welcome-jacob-young.smd'
section_path = 'C:\...\www.ziglang.org\.zig-cache\zine\s\en-US\news\s'
section file contents:
    news\migrate-to-self-hosting\index.smd
    news\carmen-the-allocgator\index.smd
    news\welcome-matthew-lugg.smd
    news\first-donor-bounty.smd
    news\announcing-donor-bounties.smd
    news\2024-financials.smd
    news\bounties-damage-open-source-projects.smd
    news\welcome-jacob-young.smd
    news\0.11.0-postponed-again.smd
    news\goodbye-cpp\index.smd
    news\financials-update.smd
    news\jakub-konka-hired-full-time\index.smd
    news\website-i18n-redesign.smd
    news\zig-0.7.1.smd
    news\fosdem-2021.smd
    news\statement-regarding-zen-programming-language.smd
    news\announcing-zig-software-foundation.smd

Notice how the path separator in md_rel_path differs from the ones in the section file contents.
Hacking around I was able to confirm that fixing this issue allows to complete a ziglang.org build on Windows.

[Atomk]

After #59 these are the remaining failures:

   │  ├─ run layout (news\welcome-jacob-young.smd) failure
   │  ├─ run layout (news\2024-financials.smd) failure
   │  ├─ run layout (news\announcing-donor-bounties.smd) failure
   │  ├─ run layout (news\first-donor-bounty.smd) failure
   │  ├─ run layout (learn\why_zig_rust_d_cpp.smd) failure
   │  ├─ run layout (learn\why_zig_rust_d_cpp.smd) failure
   │  ├─ run layout (learn\why_zig_rust_d_cpp.smd) failure
   │  ├─ run layout (learn\why_zig_rust_d_cpp.smd) failure
   │  └─ run layout (learn\why_zig_rust_d_cpp.smd) failure

I was able to work around this by replacing this code with the following lines, but it's obviously just a hack and should be properly fixed by someone who better understand the codebase (and Zig, this is my first time actually using the language)

var ref_native = try gpa.dupe(u8, ref);
if (builtin.os.tag == .windows) {
    std.mem.replaceScalar(u8, ref_native[0..], '/', std.fs.path.sep);
}

const res = try page_finder.find(.{
    .ref = .{
        .site = page_site,
        .path = ref_native,
    },
});