refactor: remove GUARDIANS constant, consolidate into guardian-data.ts

- Delete src/lib/game/constants/guardians.ts (the old static GUARDIANS constant)
- Create src/lib/game/data/guardian-data.ts with BASE_GUARDIANS (same data, new home)
- Remove GUARDIANS export from constants/index.ts
- Update all 11 files that imported GUARDIANS to use getGuardianForFloor() or BASE_GUARDIANS:
  - useGameDerived.ts, combat-actions.ts, gameStore.ts, prestigeStore.ts
  - combat-utils.ts, room-utils.ts, floor-utils.ts, spire-utils.ts
  - SpireCombatPage.tsx, SpireHeader.tsx
- Update 4 test files to use getGuardianForFloor() instead of GUARDIANS constant
- guardian-encounters.ts now imports BASE_GUARDIANS from guardian-data.ts
- Split room-utils.test.ts (505 lines) into room-utils.test.ts + room-utils-floor-state.test.ts

src/lib/game/stores/combat-actions.ts

@@ -2,7 +2,8 @@
 // Pure combat logic — no cross-store getState() calls.
 // All external data (signedPacts, etc.) is passed in as parameters.
 
-import { SPELLS_DEF, GUARDIANS, HOURS_PER_TICK } from '../constants';
+import { SPELLS_DEF, HOURS_PER_TICK } from '../constants';
+import { getGuardianForFloor } from '../data/guardian-encounters';
 import type { CombatStore, CombatState } from './combat-state.types';
 import type { SpellState } from '../types';
 import { getFloorMaxHP, getFloorElement, calcDamage, canAffordSpellCost, deductSpellCost } from '../utils';
@@ -114,16 +115,16 @@ export function processCombatTick(
 
       // Check if floor is cleared
       if (floorHP <= 0) {
-        const wasGuardian = GUARDIANS[currentFloor];
-        onFloorCleared(currentFloor, !!wasGuardian);
+        const guardian = getGuardianForFloor(currentFloor);
+        onFloorCleared(currentFloor, !!guardian);
 
         currentFloor = Math.min(currentFloor + 1, 100);
         floorMaxHP = getFloorMaxHP(currentFloor);
         floorHP = floorMaxHP;
         castProgress = 0;
 
-        if (wasGuardian) {
-          logMessages.push(`⚔️ ${wasGuardian.name} defeated!`);
+        if (guardian) {
+          logMessages.push(`\u2694\ufe0f ${guardian.name} defeated!`);
         } else if (currentFloor % 5 === 0) {
           logMessages.push(`🏰 Floor ${currentFloor - 1} cleared!`);
         }

src/lib/game/stores/gameStore.ts

@@ -4,7 +4,8 @@
 
 import { create } from 'zustand';
 import { persist } from 'zustand/middleware';
-import { TICK_MS, HOURS_PER_TICK, MAX_DAY, GUARDIANS, getStudySpeedMultiplier } from '../constants';
+import { TICK_MS, HOURS_PER_TICK, MAX_DAY, getStudySpeedMultiplier } from '../constants';
+import { getGuardianForFloor } from '../data/guardian-encounters';
 import { hasSpecial, SPECIAL_EFFECTS } from '../effects/special-effects';
 import { computeEquipmentEffects } from '../effects';
 import type { ComputedEffects } from '../effects/upgrade-effects.types';
@@ -234,7 +235,7 @@ export const useGameStore = create<GameCoordinatorStore>()(
 
         // Pact ritual progress
         if (ctx.prestige.pactRitualFloor !== null) {
-          const guardian = GUARDIANS[ctx.prestige.pactRitualFloor];
+          const guardian = getGuardianForFloor(ctx.prestige.pactRitualFloor);
           if (guardian) {
             const pactAffinityBonus = 1 - (ctx.prestige.prestigeUpgrades.pactAffinity || 0) * 0.1;
             const requiredTime = guardian.pactTime * pactAffinityBonus;
@@ -275,7 +276,8 @@ export const useGameStore = create<GameCoordinatorStore>()(
             1,
             (floor, wasGuardian) => {
               if (wasGuardian) {
-                addLog(`⚔️ ${GUARDIANS[floor]?.name || 'Guardian'} defeated! Visit the Grimoire to sign a pact.`);
+                const defeatedGuardian = getGuardianForFloor(floor);
+                addLog(`\u2694\ufe0f ${defeatedGuardian?.name || 'Guardian'} defeated! Visit the Grimoire to sign a pact.`);
               } else if (floor % 5 === 0) {
                 addLog(`🏰 Floor ${floor} cleared!`);
               }

src/lib/game/stores/prestigeStore.ts

@@ -5,7 +5,8 @@ import { create } from 'zustand';
 import { persist } from 'zustand/middleware';
 import { createSafeStorage } from '../utils/safe-persist';
 import type { Memory } from '../types';
-import { GUARDIANS, PRESTIGE_DEF } from '../constants';
+import { PRESTIGE_DEF } from '../constants';
+import { getGuardianForFloor } from '../data/guardian-encounters';
 import { ok, okVoid, fail, ErrorCode } from '../utils/result';
 import type { Result } from '../utils/result';
 
@@ -151,7 +152,7 @@ export const usePrestigeStore = create<PrestigeStore>()(
 
       startPactRitual: (floor: number, rawMana: number) => {
         const state = get();
-        const guardian = GUARDIANS[floor];
+        const guardian = getGuardianForFloor(floor);
         if (!guardian) return fail(ErrorCode.INVALID_INPUT, `No guardian at floor ${floor}`);
 
         if (!state.defeatedGuardians.includes(floor)) return fail(ErrorCode.GUARDIAN_NOT_DEFEATED, `Guardian at floor ${floor} has not been defeated`);
@@ -178,7 +179,7 @@ export const usePrestigeStore = create<PrestigeStore>()(
         const state = get();
         if (state.pactRitualFloor === null) return;
 
-        const guardian = GUARDIANS[state.pactRitualFloor];
+        const guardian = getGuardianForFloor(state.pactRitualFloor);
         if (!guardian) return;
 
         set({