Open rescue staging file in binary mode to fix Windows CRLF corruption

On Windows os.open() defaults to text mode, so os.write() of preserved
config bytes containing \r\n was translated to \r\r\n, corrupting the
staged backup and failing the retry-restore regression test. Add
O_BINARY (0 on POSIX) to the staging file open flags.

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Author: mnriem

src/specify_cli/extensions/__init__.py

@@ -1525,7 +1525,14 @@ def install_from_directory(
                     # Create the staging file with mode 0600 before writing so
                     # the preserved bytes are never transiently readable by other
                     # local users, even on a umask that would produce 0644.
-                    fd = os.open(str(staged), os.O_WRONLY | os.O_CREAT | os.O_EXCL, 0o600)
+                    # O_BINARY (0 on POSIX) is required so Windows does not open
+                    # the descriptor in text mode and translate the preserved
+                    # bytes' "\n" into "\r\n" as they are written.
+                    fd = os.open(
+                        str(staged),
+                        os.O_WRONLY | os.O_CREAT | os.O_EXCL | getattr(os, "O_BINARY", 0),
+                        0o600,
+                    )
                     try:
                         # os.write() may write fewer bytes than requested, so
                         # loop until the whole buffer is on disk — a truncated