Use wasted hashes on "Sell for Money"

src/Hacknet/HashManager.ts

@@ -113,9 +113,17 @@ export class HashManager {
     this.hashes += cost;
   }
 
-  storeHashes(numHashes: number): void {
+  /**
+   * Stores the given hashes, capping at capacity
+   * @param numHashes The number of hashes to increment
+   * @returns The number of wasted hashes (over capacity)
+   */
+  storeHashes(numHashes: number): number {
     this.hashes += numHashes;
+    let wastedHashes = this.hashes;
     this.hashes = Math.min(this.hashes, this.capacity);
+    wastedHashes -= this.hashes;
+    return wastedHashes;
   }
 
   updateCapacity(newCap: number): void {