fix(#411): QA-012 — clamp RetryOptions to sensible ranges

fetchWithRetry now clamps maxRetries>=0, baseDelayMs>=100,
backoffFactor>=1 to prevent infinite loops or zero-delay hammering.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

apps/web/src/lib/auth/fetch-with-retry.test.ts

@@ -280,4 +280,68 @@ describe("fetchWithRetry", (): void => {
     expect(global.fetch).toHaveBeenCalledTimes(3);
     expect(sleepMock).toHaveBeenCalledTimes(2);
   });
+
+  describe("RetryOptions value clamping", (): void => {
+    it("should clamp negative maxRetries to 0 (no retries)", async (): Promise<void> => {
+      const serverError = mockResponse(500);
+      vi.mocked(global.fetch).mockResolvedValueOnce(serverError);
+
+      const result = await fetchWithRetry("https://api.example.com/auth/config", undefined, {
+        maxRetries: -5,
+      });
+
+      // maxRetries clamped to 0 means only the initial attempt, no retries
+      expect(result.status).toBe(500);
+      expect(global.fetch).toHaveBeenCalledTimes(1);
+      expect(sleepMock).not.toHaveBeenCalled();
+    });
+
+    it("should clamp fractional maxRetries by flooring", async (): Promise<void> => {
+      const networkError = new TypeError("Failed to fetch");
+      const okResponse = mockResponse(200);
+      vi.mocked(global.fetch).mockRejectedValueOnce(networkError).mockResolvedValueOnce(okResponse);
+
+      const result = await fetchWithRetry("https://api.example.com/auth/config", undefined, {
+        maxRetries: 1.9,
+        baseDelayMs: 100,
+      });
+
+      // 1.9 floors to 1, so 1 initial + 1 retry = 2 attempts
+      expect(result).toBe(okResponse);
+      expect(global.fetch).toHaveBeenCalledTimes(2);
+      expect(sleepMock).toHaveBeenCalledTimes(1);
+    });
+
+    it("should clamp baseDelayMs below 100 up to 100", async (): Promise<void> => {
+      const okResponse = mockResponse(200);
+      vi.mocked(global.fetch)
+        .mockRejectedValueOnce(new TypeError("Failed to fetch"))
+        .mockResolvedValueOnce(okResponse);
+
+      await fetchWithRetry("https://api.example.com/auth/config", undefined, {
+        baseDelayMs: 0,
+      });
+
+      // baseDelayMs clamped to 100, so first retry delay = 100 * 2^0 = 100
+      expect(recordedDelays[0]).toBe(100);
+    });
+
+    it("should clamp backoffFactor below 1 up to 1 (linear delay)", async (): Promise<void> => {
+      const networkError = new TypeError("Failed to fetch");
+      const okResponse = mockResponse(200);
+      vi.mocked(global.fetch)
+        .mockRejectedValueOnce(networkError)
+        .mockRejectedValueOnce(networkError)
+        .mockResolvedValueOnce(okResponse);
+
+      await fetchWithRetry("https://api.example.com/auth/config", undefined, {
+        maxRetries: 3,
+        baseDelayMs: 200,
+        backoffFactor: 0,
+      });
+
+      // backoffFactor clamped to 1, so delays are 200*1^0=200, 200*1^1=200 (constant)
+      expect(recordedDelays).toEqual([200, 200]);
+    });
+  });
 });

apps/web/src/lib/auth/fetch-with-retry.ts

@@ -54,9 +54,9 @@ export async function fetchWithRetry(
   options?: RequestInit,
   retryOptions?: RetryOptions
 ): Promise<Response> {
-  const maxRetries = retryOptions?.maxRetries ?? DEFAULT_MAX_RETRIES;
-  const baseDelayMs = retryOptions?.baseDelayMs ?? DEFAULT_BASE_DELAY_MS;
-  const backoffFactor = retryOptions?.backoffFactor ?? DEFAULT_BACKOFF_FACTOR;
+  const maxRetries = Math.max(0, Math.floor(retryOptions?.maxRetries ?? DEFAULT_MAX_RETRIES));
+  const baseDelayMs = Math.max(100, retryOptions?.baseDelayMs ?? DEFAULT_BASE_DELAY_MS);
+  const backoffFactor = Math.max(1, retryOptions?.backoffFactor ?? DEFAULT_BACKOFF_FACTOR);
 
   let lastError: unknown = null;
   let lastResponse: Response | null = null;