Apply specific commits from another branch with git cherry-pick (including conflicts and merges)

Documented steps

1. Ensure a clean working tree, then run `git cherry-pick <commit>` — it applies the change that commit introduces and records a NEW commit for it.
2. Cherry-pick several commits at once: `git cherry-pick a b c`, or a range like `git cherry-pick master~4 master~2` (creates one new commit per source).
3. To apply all commits on master not yet in HEAD, use `git cherry-pick ..master` (equivalent to `^HEAD master`).
4. On a conflicting commit, Git sets `CHERRY_PICK_HEAD` and leaves conflict markers; resolve the files, `git add <paths>`, then `git cherry-pick --continue`.
5. Cancel a problematic pick with `git cherry-pick --abort` (returns to the pre-sequence state and clears `CHERRY_PICK_HEAD`), or skip the current commit with `--skip`.
6. When backporting between public branches, add `-x` to append a '(cherry picked from commit ...)' trailer for traceability (use `--no-edit` to skip the editor).
7. To cherry-pick a merge commit you MUST pass `--mainline <parent-number>` (parents numbered from 1) to say which side is the main line.
8. Official docs: https://git-scm.com/docs/git-cherry-pick