Phase 0: Project setup for agent-driven development

- Phaser 3 + bitECS 0.4 + TypeScript + Vite stack
- BootScene with title screen
- 6 cursor rules (project context, agent workflow, ECS, chemistry, Phaser, data)
- Vitest configured with happy-dom
- GDD, engine analysis, implementation plan, progress tracking

Co-authored-by: Cursor <cursoragent@cursor.com>

.cursor/rules/agent-workflow.mdc

@@ -0,0 +1,30 @@
+---
+description: Agent development workflow — visual feedback, testing, progress tracking
+alwaysApply: true
+---
+
+# Agent Workflow
+
+## Visual Verification
+After ANY visual change, verify via Playwright browser tools:
+1. Ensure dev server is running (`npm run dev`)
+2. Navigate to `http://localhost:5173`
+3. Take screenshot to see result
+4. Check browser console for errors
+5. Fix issues before moving on
+
+## Testing Strategy
+- **Chemistry, ecology, math** — write vitest tests FIRST, then implement
+- **Visual/rendering** — verify via Playwright screenshots
+- Run `npm run test:run` after logic changes
+
+## After Completing a Task
+1. Verify it works (test or screenshot)
+2. Update `PROGRESS.md` — mark task complete, add date
+3. Check `IMPLEMENTATION-PLAN.md` for what's next
+
+## Code Standards
+- TypeScript strict mode — no `any`, no unsafe `as` casts
+- Pure functions for ECS systems
+- Descriptive variable names (not `x`, `tmp`, `data`)
+- Comments explain WHY, not WHAT