feat: SDLC database separation for CI/testing (#35)

## Summary
- Fix `isProductionDatabase()` to allow CI database (`euchre_camp_ci`)
- Add database schema reset before CI test runs
- Create `global.teardown.ts` for cleanup (CI: full reset, dev/prod: selective cleanup)
- Add `acceptance-tests` job to PR workflow with CI database
- Create `sync-prod-to-dev.js` script for one-way prod→dev sync
- Add `just` recipes: `sync-dev`, `test-prod`, `reset-ci-db`
- Store credentials in `.credentials` (gitignored) with unique CI user

## Testing
Verified against CI database:
- Schema reset works
- Migrations apply correctly
- Test users created successfully
- 219 tests pass (slow but working)

## Next Steps
- Set `CI_DATABASE_URL` as Gitea repository variable

Reviewed-on: #35
Co-authored-by: David Gwilliam <dhgwilliam@gmail.com>
Co-committed-by: David Gwilliam <dhgwilliam@gmail.com>

e2e/epic3-rankings.test.ts

@@ -0,0 +1,47 @@
+/**
+ * Epic 3: Rankings & Public Data
+ * Acceptance Test: Player Rankings Page
+ * 
+ * User Story: As a visitor, I want to view player rankings so that I can see top players
+ * 
+ * Acceptance Criteria:
+ * - Sortable rankings table
+ * - Columns: Rank, Name, Elo, Win Rate, Games Played
+ * - Search/filter functionality
+ * - Pagination
+ */
+
+import { test, expect } from '@playwright/test';
+
+test.describe('Epic 3: Rankings Page', () => {
+  test('Rankings page loads and displays rankings table', async ({ page }) => {
+    await page.goto('http://localhost:3000/rankings');
+
+    // Check page title or heading
+    await expect(page.locator('h1, h2')).toContainText(/rankings?/i);
+
+    // Check for rankings table
+    await expect(page.locator('table')).toBeVisible();
+  });
+
+  test('Rankings table displays player columns', async ({ page }) => {
+    await page.goto('http://localhost:3000/rankings');
+
+    // Check for expected column headers
+    const table = page.locator('table');
+    await expect(table).toBeVisible();
+
+    // Check for column headers (may vary based on implementation)
+    const headerCount = await page.locator('th').count();
+    expect(headerCount).toBeGreaterThan(0);
+  });
+
+  test('Rankings page is publicly accessible (no login required)', async ({ page }) => {
+    // Navigate directly to rankings without logging in
+    await page.goto('http://localhost:3000/rankings');
+
+    // Page should load without redirecting to login
+    await expect(page).toHaveURL(/.*rankings.*/);
+    await expect(page.locator('body')).toBeVisible();
+  });
+});