test: fix mock leakage in db tests

src/lib/db.test.ts

@@ -1,18 +1,5 @@
 import { describe, it, expect, mock, beforeEach } from "bun:test";
 
-// Mock shutdown module before importing db
-mock.module("./shutdown", () => {
-    let shuttingDown = false;
-    let transactions = 0;
-    return {
-        isShuttingDown: () => shuttingDown,
-        setShuttingDown: (v: boolean) => { shuttingDown = v; },
-        incrementTransactions: () => { transactions++; },
-        decrementTransactions: () => { transactions--; },
-        getActiveTransactions: () => transactions,
-    };
-});
-
 // Mock DrizzleClient
 mock.module("./DrizzleClient", () => ({
     DrizzleClient: {
@@ -21,11 +8,15 @@ mock.module("./DrizzleClient", () => ({
 }));
 
 import { withTransaction } from "./db";
-import { setShuttingDown, getActiveTransactions } from "./shutdown";
+import { setShuttingDown, getActiveTransactions, decrementTransactions } from "./shutdown";
 
 describe("db withTransaction", () => {
     beforeEach(() => {
         setShuttingDown(false);
+        // Reset transaction count
+        while (getActiveTransactions() > 0) {
+            decrementTransactions();
+        }
     });
 
     it("should allow transactions when not shutting down", async () => {