chore: add GitHub templates and CI workflow (#7)

- Add issue templates (feature, bug, infra, docs)
- Add PR template
- Add CI workflow (lint, build, test)

🤖 Generated with Claude Code (https://claude.com/claude-code)

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

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,26 @@
+---
+name: Feature Request
+about: Propose a new feature or capability
+title: "[Feature] "
+labels: type:feature, status:backlog
+assignees: ''
+---
+
+## Summary
+<!-- One-sentence description of the feature -->
+
+## Problem / Motivation
+<!-- What problem does this solve? Why do we need it? -->
+
+## Proposed Solution
+<!-- How should this work? Be specific. -->
+
+## Alternatives Considered
+<!-- What other approaches did you consider? Why not those? -->
+
+## Acceptance Criteria
+- [ ] Criterion 1
+- [ ] Criterion 2
+
+## Additional Context
+<!-- Screenshots, links, related issues -->