chore: add adopt-upstream-pr skill

Add skill for bringing existing upstream PRs into the philips branch
for early internal deployment.

Signed-off-by: Brend Smits <brend.smits@philips.com>

Author: Brend-Smits

.github/copilot-instructions.md

@@ -36,4 +36,4 @@ Never create tags in the upstream `vX.Y.Z` format on this fork.
 
 ## Skills
 
-Use `/sync-upstream`, `/philips-release`, `/urgent-fix`, `/upstream-pr-merged`, or `/monthly-hygiene` in Copilot chat for step-by-step procedures.
+Use `/sync-upstream`, `/philips-release`, `/urgent-fix`, `/adopt-upstream-pr`, `/upstream-pr-merged`, or `/monthly-hygiene` in Copilot chat for step-by-step procedures.

.github/skills/adopt-upstream-pr/SKILL.md

@@ -0,0 +1,103 @@
+---
+name: adopt-upstream-pr
+description: 'Adopt an existing upstream PR into the philips branch. Use when: cherry-picking an open upstream PR for early deployment, bringing an existing PR branch into the fork, fast-tracking a PR that is pending upstream review.'
+---
+
+# Adopt Upstream PR
+
+Bring an existing upstream PR into the `philips` branch for immediate internal use, without waiting for upstream to merge it.
+
+## When to Use
+
+- An upstream PR is open but not yet merged, and you need the change now
+- The PR branch already exists (on upstream, a personal fork, or the Philips fork)
+- You want to deploy the change internally while it continues through upstream review
+
+## Prerequisites
+
+- An open upstream PR number (e.g. `github-aws-runners/terraform-aws-github-runner#5031`)
+- The PR branch must be accessible (public repo or you have access)
+
+## Procedure
+
+Given an upstream PR URL like `https://github.com/github-aws-runners/terraform-aws-github-runner/pull/5031`:
+
+1. **Extract PR metadata:**
+   ```bash
+   # Get the PR branch, title, and head repo
+   gh pr view 5031 --repo github-aws-runners/terraform-aws-github-runner \
+     --json headRefName,title,headRepository,headRepositoryOwner,commits
+   ```
+
+2. **Fetch the PR branch into the fork:**
+   ```bash
+   cd <fork-clone>
+   git fetch origin philips
+   git checkout philips
+   git pull origin philips
+
+   # If PR is on the same repo (upstream):
+   git fetch upstream <branch-name>
+
+   # If PR is on a personal fork (e.g. your own):
+   git fetch https://github.com/<owner>/terraform-aws-github-runner.git <branch-name>
+   ```
+
+3. **Cherry-pick or rebase the PR commits onto philips:**
+   ```bash
+   # Option A: Single commit — cherry-pick
+   git cherry-pick <commit-sha>
+
+   # Option B: Multiple commits — cherry-pick range
+   git cherry-pick <first-commit>^..<last-commit>
+
+   # Option C: Squash into one commit
+   git merge --squash FETCH_HEAD
+   git commit -s -m "feat: <PR title>
+
+   Upstream-PR: github-aws-runners/terraform-aws-github-runner#<number>"
+   ```
+
+   **The `Upstream-PR:` trailer is mandatory.** This marks the commit as temporary — it will be removed once the upstream PR is merged.
+
+4. **Verify the philips branch:**
+   ```bash
+   git log --oneline origin/main..philips
+   ```
+   Should show infrastructure commits + the new upstream-bound commit.
+
+5. **Push:**
+   ```bash
+   git push origin philips --force-with-lease
+   ```
+
+6. **Tag a release if needed:**
+   ```bash
+   # Determine the base upstream version
+   git describe --tags --abbrev=0 origin/main   # e.g. v7.5.0
+   git tag philips-v7.5.0 philips
+   git push origin philips-v7.5.0
+   ```
+   The release workflow triggers automatically.
+
+## Quick Reference
+
+```bash
+# Full one-liner for a single-commit PR from your own fork:
+PR_NUM=5031
+PR_URL="https://github.com/github-aws-runners/terraform-aws-github-runner/pull/${PR_NUM}"
+BRANCH=$(gh pr view "$PR_NUM" --repo github-aws-runners/terraform-aws-github-runner --json headRefName -q .headRefName)
+OWNER=$(gh pr view "$PR_NUM" --repo github-aws-runners/terraform-aws-github-runner --json headRepositoryOwner -q .headRepositoryOwner.login)
+
+git checkout philips && git pull origin philips
+git fetch "https://github.com/${OWNER}/terraform-aws-github-runner.git" "$BRANCH"
+git merge --squash FETCH_HEAD
+git commit -s -m "feat: $(gh pr view "$PR_NUM" --repo github-aws-runners/terraform-aws-github-runner --json title -q .title)
+
+Upstream-PR: github-aws-runners/terraform-aws-github-runner#${PR_NUM}"
+git push origin philips --force-with-lease
+```
+
+## After Upstream Merges
+
+Once the PR lands in upstream `main`, follow the `/upstream-pr-merged` skill to drop the commit from `philips`.