[TASK] Overhaul and shorten "Contribute to system extensions"

[linawolf]

It is mainly explained in the Core contribution guide

[github-actions]

The backport to documentation-draft failed:

The process '/usr/bin/git' failed with exit code 1

stderr

error: could not apply 13e1a60... [TASK] Overhaul and shorten "Contribute to system extensions"
hint: After resolving the conflicts, mark them with
hint: "git add/rm <pathspec>", then run
hint: "git cherry-pick --continue".
hint: You can instead skip this commit with "git cherry-pick --skip".
hint: To abort and get back to the state before "git cherry-pick",
hint: run "git cherry-pick --abort".

stdout

Auto-merging Documentation/WritingDocForExtension/ContributeToSystemExtension.rst
CONFLICT (content): Merge conflict in Documentation/WritingDocForExtension/ContributeToSystemExtension.rst

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-documentation-draft documentation-draft
# Navigate to the new working tree
cd .worktrees/backport-documentation-draft
# Create a new branch
git switch --create backport-382-to-documentation-draft
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick 13e1a60d7795da47ff7ad93d5e0e77f7c4307797
# Push it to GitHub
git push --set-upstream origin backport-382-to-documentation-draft
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-documentation-draft

Then, create a pull request where the base branch is documentation-draft and the compare/head branch is backport-382-to-documentation-draft.