includeAllFiles can add a duplicate placeholder on Windows when path casing differs #1018

While working on #360, a review turned up a related edge case in includeAllFiles (lib/task-utils.ts) that seemed worth tracking on its own rather than folding into that fix.

What happens

To decide whether a globbed file is already covered, includeAllFiles converts each covered entry's path to forward slashes and compares it to the tinyglobby path with an exact, case-sensitive string match. Windows paths aren't case-sensitive, though. So if the two sides disagree only on casing, for example the drive letter (c:\proj\src\a.js from the instrumenter vs C:/proj/src/a.js from the glob), the file isn't recognized as covered and gets a second, empty placeholder entry.

Why it matters

The same file then shows up twice in the report, once with real coverage and once at 0%. That drags the totals down and can make --check-coverage fail.

Status

I haven't reproduced this in a real run yet. It comes from reading the code, so the first step is confirming which setups actually produce mismatched casing (Git Bash vs cmd.exe working directories are a likely suspect). If it's real, a fix could compare a case-folded form of the path on Windows only, leaving POSIX matching untouched.