Add First 60 Days section to onboarding checklist

[olivia499]

No description provided.

[olivia499]

This looks fine.

[hannahstulberg]

Hey @olivia499 — thanks for going through the GitHub 101 exercise!

I can't merge this PR as-is because it edits acme/playbooks/onboarding-checklist.md, which is outside the scope of the contribution exercise. The practice files in acme/ are there for you to experiment with locally, but PRs back to this repo should only include either:

• A new takeaway file at takeaways/olivia499.md, or
• An entry appended to community-board.md

(See the "Your Turn: Submit Your First PR" section of the article — line 1151 in guides/github-101.md.)

The good news is this is an easy fix and a chance to practice the workflow one more time:

1. Open Claude Code in your fork
2. Ask: "Sync my fork with sidwyn/acme-ops, then create a new branch off main and add takeaways/olivia499.md with one thing I learned from the GitHub 101 article. Commit and push, then open a PR."
3. I'll merge it right away

Closing this one for now — your branch and commits aren't lost, just the open PR. Looking forward to your takeaway!