chore: add org baseline (templates, CI, labels) (#11)

Org-wide bootstrap. Adds issue/PR templates, CI workflow, and labels. 🤖
Generated with Claude Code

Co-authored-by: Alexa Louise <YOUR_REAL_EMAIL@EXAMPLE.COM>
Co-authored-by: Claude <noreply@anthropic.com>

.github/PULL_REQUEST_TEMPLATE.md

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+## Summary
+<!-- What does this PR do? One paragraph max. -->
+
+## Changes
+<!-- Bulleted list of specific changes -->
+-
+
+## Type
+<!-- Check one -->
+- [ ] Feature
+- [ ] Bug fix
+- [ ] Infrastructure / CI
+- [ ] Documentation
+- [ ] Refactor
+- [ ] Config change
+
+## Tests
+<!-- How was this tested? -->
+- [ ] Unit tests pass
+- [ ] Integration tests pass
+- [ ] Manual testing (describe below)
+- [ ] N/A (docs only)
+
+**Manual testing steps:**
+
+
+## Risk / Impact
+<!-- What could go wrong? What's the blast radius? -->
+- Risk level: Low / Medium / High
+- Affected services:
+
+## Checklist
+- [ ] Code follows project conventions
+- [ ] No secrets or credentials committed
+- [ ] README updated (if applicable)
+- [ ] This is a single logical change (atomic PR)
+
+## Related Issues
+<!-- Closes #123, Relates to #456 -->