Support specifying commit hash with -c option

[kl2400033266]

Allow users to pass a specific commit hash with the -c option instead of always using HEAD.

Changes:

• Modified the option spec to accept a value with -c option (c,commit=)
• Added commit_hash variable to store the provided commit hash
• Updated option parsing to capture the commit hash argument
• Updated commit URL generation to use provided hash or fallback to HEAD

Usage: git open -c # Open specific commit git open -c # Open current commit (HEAD)