Fix type errors: remove unused bcryptRounds, align test with argon2 API

src/lib/auth/password.test.ts

@@ -51,13 +51,10 @@ describe("hashPassword (PASSWORD_HASH=argon2id)", () => {
 	});
 });
 
-describe("bcrypt", () => {
-	it("verifies a bcrypt hash and accepts the PHP $2y$ prefix", async () => {
-		mockEnv.BCRYPT_ROUNDS = 4;
-		const h = await bcryptHash("hunter2", 4);
+describe("argon2", () => {
+	it("verifies an argon2 hash and round-trips", async () => {
+		const h = await bcryptHash("hunter2");
 		expect(await verifyPassword("hunter2", h)).toBe(true);
-		const phpStyle = h.replace(/^\$2[ab]\$/, "$2y$");
-		expect(await verifyPassword("hunter2", phpStyle)).toBe(true);
 		expect(await verifyPassword("nope", h)).toBe(false);
 	});
 });

src/lib/auth/password.ts

@@ -19,9 +19,6 @@ function argon2Params() {
 	} as const;
 }
 
-function bcryptRounds(): number {
-	return env.BCRYPT_ROUNDS;
-}
 
 // Which algorithm hashPassword() emits for NEW/upgraded passwords.
 //   - "bcrypt"  (DEFAULT): 60-char $2y$ hash. Fits varchar(255) users.password.