[xyrolle]

Fixes #169

With withSymlinks({ resolvePaths: false }), isRecursive treated one symlink target as inside another when its path merely started with the other's as a string, so a link to /x/shared-other inside a link to /x/shared was skipped as recursive. It now compares whole path segments (isInside), after normalizing the target, since a custom fs can return / on Windows. This keeps the existing rule that equal, ancestor and descendant targets count as recursive; only siblings whose names share a prefix change.

Test: a symlinks.test.ts case with root/src -> shared and shared/alias -> shared-other, for both sync and withPromise. It fails without the change.

On master (790c182), 19 tests already fail without this change, and the same 19 fail with it. Applied on v6.5.0, all 107 pass. tsc --noEmit, npm run build and Prettier pass on the branch. #162 moves these tests off mock-fs; if it lands first, I'll move this case to its fixtures.