"--version" option does not produce output matching an existing git tag

Bug Report

$ mypy --version
mypy 1.15.0 (compiled: yes)

This version output does not match an existing tag in git.

https://github.com/python/mypy/tags
https://github.com/python/mypy/releases/tag/v1.15.0

I would expect either the --version option to return the version number with a "v" prefix or the git tags to omit the "v" prefix to match the version output.

The existing behavior causes issues where other tools or users are using the --version output to point to a git tag (e.g., when defining a pre-commit hook, or e.g., when aggregating versions of many linters and formatters like in super-linter).

related issue: https://github.com/super-linter/super-linter/issues/6826

Your Environment

• Mypy version used: v1.15.0
• Mypy command-line flags: --version
• Mypy configuration options from mypy.ini (and other config files): N/A
• Python version used: 3.12

Start by running the reported mypy --version command and tracing the CLI entry point that formats its version output. Compare the result with the existing v1.15.0 tag, then verify that the chosen convention is consistent and covered by an appropriate version-output check.