Implement pit cherry-pick

[BIJJUDAMA]

Problem:

There is no way to apply the changes from a specific commit to the current branch without merging the entire history of that commit.

Fix:

Implement pit cherry-pick <commit> to calculate the diff of a commit and apply it as a new commit on the current branch.

Technical Detail:

This requires calculating the diff between <commit> and <commit>^ (parent). Then, we must patch the current working directory with this diff. If there are conflicts, we report them (similar to merge). Finally, we automatically commit the result.

Behaviour:

• pit cherry-pick <hash>
  Applies the changes introduced by <hash> onto the current HEAD and creates a new commit.

Note

• Must work with tags

[priyansh-narang2308]

/assign

[Devpool-soc]

Alright @priyansh-narang2308! Consider yourself officially assigned as now. If you are thinking, "Whoa, hold up, I didn't sign up for this," no worries, just yell "/unassign" and we can pretend this never happened. But if you are sticking around, just know your clock for this ticks out on: 2026-01-17. Don't screw it up :)