[v2] Double-quote Windows alias command args if metacharacters present

[hssyoo]

_windows_shell_quote() only escapes for the MSVC C runtime argv parser (backslashes and double quotes) but
does not account for cmd.exe metacharacters. When ExternalAliasCommand passes user-supplied arguments through subprocess.call(command, shell=True), the string is interpreted by cmd.exe before reaching the target process, meaning metacharacters aren't properly escaped.

This PR fixes the issue by double-quoting the alias value string when shell=True and cmd.exe metacharacters are present, automatically treating metacharacters as literals.

Ideally we could collapse _windows_argv_quote and _windows_cmd_shell_quote into a single function, but I'm hesitant to change the code path for other CLI features that use compat_shell_quote, especially features that don't spawn a subprocess with shell=True like ec2-instance-connect ssh.

NOTE: %VAR% expansion and !VAR! delayed expansion cannot be reliably escaped inside double quotes in cmd.exe /c. %% doubling only works in batch file mode. There is no known reliable escape for % or ! inside double quotes on the command line.