Add minimum git version requirement check

[jovnc]

Fixes git-mastery/git-mastery#60

• git sparse-checkout and git clone <...> --sparse are features that are introduced in 2.25.0
• --filter in sparse checkout (which we use in app) is also not working until 2.28.0 (source: Sparse checkout not working with git version between 2.25 and 2.28 actions/checkout#1386)

Would prefer not to set too strict restrictions on the git version (eg. must always be latest version, etc.) as additional features may not be required for the app, and thus it's not a requirement for users to update their git.

[Copilot]

Pull request overview

This PR adds a minimum Git version requirement check to ensure users have Git 2.28.0 or later installed, which is necessary for sparse checkout functionality with the --filter option used by the application.

Changes:

• Added a new Version.parse() method to parse plain version strings without a 'v' prefix
• Replaced is_git_installed() with get_git_version() that returns the installed Git version or None
• Integrated version checking into the check git command to validate the minimum version requirement

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
app/utils/version.py	Added parse() method to parse plain version strings (e.g., '1.2.3') alongside existing parse_version_string() for 'v'-prefixed strings
app/utils/git.py	Introduced MIN_GIT_VERSION constant (2.28.0) and replaced boolean is_git_installed() with get_git_version() that extracts version from git --version output
app/commands/check/git.py	Updated git check command to retrieve git version, validate it meets minimum requirement, and display appropriate error messages

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[desmondwong1215]

LGTM! I have tested it and it works as intended.