Phase 7: structured ruleset data (Open5e 5e + Foundry PF2e classes)

- Scrapers scripts/fetch_open5e.ts (classes/races/backgrounds/feats, CC-BY/OGL) and
  fetch_foundry_pf2e.ts (25 PF2e classes, OGL/ORC) → normalized JSON in src/data/srd
  + public/data/pf2e/classes.json.
- src/lib/ruleset/normalize.ts: pure, tested normalizers → unified RulesetClass
  (hit die, key abilities, saves/ranks, perception, skills, caster, subclasses, profs).
- compendium loaders (loadClasses/loadRaces5e/loadBackgrounds5e) + a "Classes" tab for
  both systems (ClassDetail) with full stats; Bestiary stays the default category.
- Data-source attribution in Settings. Feeds the Phase 5 builder.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

e2e/compendium.spec.ts

@@ -21,6 +21,12 @@ test('compendium: browse 5e categories, switch to PF2e, cross-link a spell', asy
   // Compendium → 5e categories exist (Feats is a new one)
   await page.getByRole('link', { name: 'Compendium' }).click();
   await expect(page.getByRole('button', { name: 'Feats' })).toBeVisible();
+
+  // Classes category (Open5e data) lists classes with detail
+  await page.getByRole('button', { name: 'Classes', exact: true }).click();
+  await page.getByRole('button', { name: /^Wizard/ }).first().click();
+  await expect(page.getByText('Hit die')).toBeVisible();
+  await expect(page.getByText(/School of Evocation/)).toBeVisible();
   await page.getByRole('button', { name: 'Conditions' }).click();
   await expect(page.getByText(/results/)).toBeVisible();