Add --version flag to display mxmake version

Adds -v/--version command line option that prints the current
mxmake version using the auto-generated version from hatch-vcs.

Author: jensens

CHANGES.md

@@ -5,6 +5,9 @@
 - Enhancement: Use tables in the generated sphinx code for topic/domains.
   [jensens, 02-11-2025]
 
+- Feature: Add `--version` (`-v`) command line flag to display mxmake version.
+  [jensens, 02-11-2025]
+
 ## 2.0.0 (2025-10-24)
 
 - **Breaking**: Drop Python 3.9 support. Minimum Python version is now 3.10.

src/mxmake/main.py

@@ -1,3 +1,4 @@
+from ._version import __version__
 from .helpgen import print_help
 from .parser import MakefileParser
 from .templates import ci_template
@@ -27,6 +28,12 @@
 
 
 parser = argparse.ArgumentParser()
+parser.add_argument(
+    "-v",
+    "--version",
+    action="version",
+    version=f"%(prog)s {__version__}",
+)
 command_parsers = parser.add_subparsers(dest="command", required=True)