feat: implement golemancy combat system (spec §6, §9)

- Add ActiveGolem interface and activeGolems to GolemancyState
- Add maxRoomDuration to all 12 golem definitions
- Create golem-combat-actions.ts with pure golem combat logic (summoning, maintenance, attacks, room-duration)
- Create golem-combat.ts pipeline for golem combat setup
- Wire golem maintenance and attacks into processCombatTick
- Wire golem summoning into advanceRoomOrFloor on room entry
- Wire golem room-duration countdown into onFloorCleared callback
- Update combat-actions tests for new processCombatTick signature
- All 921 tests pass, all files under 400-line limit

Closes #259

src/lib/game/data/golems/base-golems.ts

@@ -26,5 +26,6 @@ export const BASE_GOLEMS: Record<string, GolemDef> = {
       level: 2,
     },
     tier: 1,
+    maxRoomDuration: 3,
   },
 };

src/lib/game/data/golems/elemental-golems.ts

@@ -25,6 +25,7 @@ export const ELEMENTAL_GOLEMS: Record<string, GolemDef> = {
       manaType: 'metal',
     },
     tier: 2,
+    maxRoomDuration: 3,
   },
   
   // Crystal Golem - Crystal mana variant
@@ -46,6 +47,7 @@ export const ELEMENTAL_GOLEMS: Record<string, GolemDef> = {
       manaType: 'crystal',
     },
     tier: 3,
+    maxRoomDuration: 4,
   },
   
   // Sand Golem - Sand mana variant
@@ -67,6 +69,7 @@ export const ELEMENTAL_GOLEMS: Record<string, GolemDef> = {
       manaType: 'sand',
     },
     tier: 2,
+    maxRoomDuration: 3,
     specialAbilities: [
       { name: 'Sandstorm', description: 'Hits multiple enemies (AoE)' },
     ],

src/lib/game/data/golems/hybrid-golems.ts

@@ -25,6 +25,7 @@ export const HYBRID_GOLEMS: Record<string, GolemDef> = {
       levels: [5, 5],
     },
     tier: 3,
+    maxRoomDuration: 4,
     specialAbilities: [
       { name: 'Burn', description: 'Burns enemies over time (DoT)' },
     ],
@@ -50,6 +51,7 @@ export const HYBRID_GOLEMS: Record<string, GolemDef> = {
       levels: [5, 5],
     },
     tier: 3,
+    maxRoomDuration: 4,
     specialAbilities: [
       { name: 'Lightning Speed', description: 'Extremely fast attacks bonus' },
     ],
@@ -75,6 +77,7 @@ export const HYBRID_GOLEMS: Record<string, GolemDef> = {
       levels: [5, 5],
     },
     tier: 4,
+    maxRoomDuration: 5,
     specialAbilities: [
       { name: 'Devastating Strike', description: 'Devastating single-target damage' },
     ],
@@ -100,6 +103,7 @@ export const HYBRID_GOLEMS: Record<string, GolemDef> = {
       levels: [5, 5],
     },
     tier: 4,
+    maxRoomDuration: 5,
     specialAbilities: [
       { name: 'Piercing Beams', description: 'Channels light into piercing beams' },
     ],
@@ -125,6 +129,7 @@ export const HYBRID_GOLEMS: Record<string, GolemDef> = {
       levels: [5, 5],
     },
     tier: 3,
+    maxRoomDuration: 4,
     specialAbilities: [
       { name: 'Flow', description: 'Flows around defenses, fast & hard to dodge' },
     ],
@@ -150,6 +155,7 @@ export const HYBRID_GOLEMS: Record<string, GolemDef> = {
       levels: [5, 5],
     },
     tier: 4,
+    maxRoomDuration: 5,
     specialAbilities: [
       { name: 'Void Infusion', description: 'Earth infused with void energy' },
     ],

src/lib/game/data/golems/types.ts

@@ -39,5 +39,6 @@ export interface GolemDef {
     levels?: number[];
   };
   tier: number;                  // Power tier (1-4)
+  maxRoomDuration: number;         // Rooms before golem disappears (spec §9.6)
   specialAbilities?: { name: string; description: string }[]; // Special abilities
 }