Fix BUG 2: Set currentAction to 'study' when starting skill or spell study

The startStudyingSkill() and startStudyingSpell() functions in skillStore.ts
were setting currentStudyTarget but not updating currentAction in combatStore.
Added useCombatStore.getState().setAction('study') calls to both functions
so the game tick properly processes study progress.

src/lib/game/stores/combatStore.ts

@@ -77,6 +77,8 @@ export interface CombatState {
   setIsDescending: (descending: boolean) => void;
   climbDownFloor: () => void;
   exitSpireMode: () => void;
+  startClimbUp: () => void;
+  startClimbDown: () => void;
   
   // Golemancy
   toggleGolem: (golemId: string) => void;
@@ -254,6 +256,10 @@ export const useCombatStore = create<CombatState>()(
         set({ spireMode: false, climbDirection: null, isDescending: false });
       },
       
+      startClimbUp: () => set({ climbDirection: 'up', currentAction: 'climb' }),
+      
+      startClimbDown: () => set({ climbDirection: 'down', currentAction: 'climb' }),
+      
       // Golemancy
       toggleGolem: (golemId: string) => {
         set((s) => {

src/lib/game/stores/skillStore.ts

@@ -6,6 +6,7 @@ import { persist } from 'zustand/middleware';
 import { SKILLS_DEF, getStudySpeedMultiplier, getStudyCostMultiplier } from '../constants';
 import type { StudyTarget, SkillUpgradeChoice } from '../types';
 import { SKILL_EVOLUTION_PATHS, getBaseSkillId } from '../skill-evolution';
+import { useCombatStore } from './combatStore';
 
 export interface SkillState {
   // Skills
@@ -131,6 +132,8 @@ export const useSkillStore = create<SkillState>()(
           },
         });
         
+        useCombatStore.getState().setAction('study');
+        
         return { started: true, cost: isAlreadyPaid ? 0 : cost };
       },
       
@@ -147,6 +150,8 @@ export const useSkillStore = create<SkillState>()(
           },
         });
         
+        useCombatStore.getState().setAction('study');
+        
         // Spell study has no mana cost upfront - cost is paid via study time
         return { started: true, cost: 0 };
       },