Task 1: Add Hybrid Skills - Pact-Weaving, Guardian Constructs, Enchanted Golemancy

- Implement Pact-Weaving (Invoker + Enchanter) hybrid skill
  * Paths: The Weaver, The Warp, The World-Weaver
  * Weave Guardian essence into weapon enchantments/world-effects
  * Requires: Invoker 5+, Enchanter 5+

- Implement Guardian Constructs (Fabricator + Invoker) hybrid skill
  * Paths: The Architect, The Monumentalist, The Eternal
  * Only 1 active at a time, vastly more durable
  * Requires: Fabricator 5+, Invoker 5+

- Implement Enchanted Golemancy (Fabricator + Enchanter) hybrid skill
  * Paths: The Battle-Smith, The Enchanter-Smith, The Spell-Smith
  * Imbue golems with elemental spell logic
  * Requires: Fabricator 5+, Enchanter 5+

- All 512 tests passing

src/lib/game/__tests__/skills.test.ts

@@ -509,7 +509,7 @@ describe('Integration Tests', () => {
   });
 
   it('all skills should have valid categories', () => {
-    const validCategories = ['mana', 'study', 'ascension', 'enchant', 'effectResearch', 'invocation', 'pact', 'fabrication', 'golemancy', 'research', 'craft'];
+    const validCategories = ['mana', 'study', 'ascension', 'enchant', 'effectResearch', 'invocation', 'pact', 'fabrication', 'golemancy', 'research', 'craft', 'hybrid'];
     Object.values(SKILLS_DEF).forEach(skill => {
       expect(validCategories).toContain(skill.cat);
     });