fix: reject negative amounts in spendRawMana, spendElementMana, addRawMana, addElementMana, and unlockElement to prevent mana exploit

docs/circular-deps.txt

@@ -1,5 +1,5 @@
 # Circular Dependencies
-Generated: 2026-06-10T11:13:04.646Z
+Generated: 2026-06-10T18:50:03.343Z
 Found: 3 circular chain(s) — these MUST be fixed before modifying involved files.
 
 1. 1) stores/golem-combat-actions.ts > stores/golem-combat-helpers.ts

docs/dependency-graph.json

@@ -1,6 +1,6 @@
 {
   "_meta": {
-    "generated": "2026-06-10T11:13:02.589Z",
+    "generated": "2026-06-10T18:50:01.087Z",
     "description": "Import dependency graph for src/lib/game. Keys are files, values are arrays of files they import.",
     "usage": "To find what a file affects, search for its path in the VALUES. To find what a file depends on, look at its KEY entry."
   },

src/lib/game/stores/manaStore.ts

@@ -76,6 +76,7 @@ export const useManaStore = create<ManaStore>()(
       },
 
       addRawMana: (amount: number, maxMana: number) => {
+        if (amount < 0) return;
         set((state) => ({
           rawMana: Math.min(state.rawMana + amount, maxMana),
           totalManaGathered: state.totalManaGathered + amount,
@@ -84,7 +85,7 @@ export const useManaStore = create<ManaStore>()(
 
       spendRawMana: (amount: number) => {
         const state = get();
-        if (state.rawMana < amount) return false;
+        if (amount < 0 || state.rawMana < amount) return false;
         set({ rawMana: state.rawMana - amount });
         return true;
       },
@@ -102,6 +103,7 @@ export const useManaStore = create<ManaStore>()(
 
       unlockElement: (element: string, cost: number) => {
         const state = get();
+        if (cost < 0) return fail(ErrorCode.INVALID_INPUT, `Unlock cost cannot be negative`);
         if (state.elements[element]?.unlocked) return fail(ErrorCode.INVALID_INPUT, `Element ${element} is already unlocked`);
         if (state.rawMana < cost) return fail(ErrorCode.INSUFFICIENT_MANA, `Need ${cost} raw mana, have ${state.rawMana}`);
 
@@ -116,6 +118,7 @@ export const useManaStore = create<ManaStore>()(
       },
 
       addElementMana: (element: string, amount: number, max: number) => {
+        if (amount < 0) return;
         set((state) => {
           const elem = state.elements[element];
           if (!elem) return state;
@@ -129,6 +132,7 @@ export const useManaStore = create<ManaStore>()(
         const state = get();
         const elem = state.elements[element];
         if (!elem) return fail(ErrorCode.INVALID_ELEMENT, `Element ${element} does not exist`);
+        if (amount < 0) return fail(ErrorCode.INVALID_INPUT, `Cannot spend negative mana`);
         if (elem.current < amount) return fail(ErrorCode.INSUFFICIENT_MANA, `Need ${amount} ${element} mana, have ${elem.current}`);
 
         set({ elements: { ...state.elements, [element]: { ...elem, current: elem.current - amount } } });