std.os.windows: handle OBJECT_NAME_INVALID in OpenFile (#19288)

It's been seen on Windows 11 (22H2) Build 22621.3155 that NtCreateFile
will return the OBJECT_NAME_INVALID error code with certain path names.
The path name we saw this with started with `C:Users` (rather than
`C:\Users`) and also contained a `$` character.  This PR updates our
OpenFile wrapper to propagate this error code as `error.BadPathName`
instead of making it `unreachable`.

see marler8997/zigup#114 (comment)

Author: marler8997

lib/std/os/windows.zig

@@ -42,6 +42,7 @@ pub const OpenError = error{
     WouldBlock,
     NetworkNotFound,
     AntivirusInterference,
+    BadPathName,
 };
 
 pub const OpenFileOptions = struct {
@@ -120,7 +121,7 @@ pub fn OpenFile(sub_path_w: []const u16, options: OpenFileOptions) OpenError!HAN
         );
         switch (rc) {
             .SUCCESS => return result,
-            .OBJECT_NAME_INVALID => unreachable,
+            .OBJECT_NAME_INVALID => return error.BadPathName,
             .OBJECT_NAME_NOT_FOUND => return error.FileNotFound,
             .OBJECT_PATH_NOT_FOUND => return error.FileNotFound,
             .BAD_NETWORK_PATH => return error.NetworkNotFound, // \\server was not found