fix(test): add optional chaining to mock restore calls in stdio tests

Fixed TypeError when calling mockRestore() on potentially undefined spies
in afterEach hooks. Added optional chaining (?.) to safely restore mocks.

Author: jdalton

test/stdio/stderr.test.ts

@@ -40,9 +40,9 @@ describe('stdio/stderr', () => {
 
   afterEach(() => {
     // Restore spies
-    writeSpy.mockRestore()
-    cursorToSpy.mockRestore()
-    clearLineSpy.mockRestore()
+    writeSpy?.mockRestore()
+    cursorToSpy?.mockRestore()
+    clearLineSpy?.mockRestore()
 
     // Restore original properties
     Object.defineProperty(stderr, 'isTTY', {

test/stdio/stdout.test.ts

@@ -47,10 +47,10 @@ describe('stdio/stdout', () => {
 
   afterEach(() => {
     // Restore spies
-    writeSpy.mockRestore()
-    cursorToSpy.mockRestore()
-    clearLineSpy.mockRestore()
-    clearScreenDownSpy.mockRestore()
+    writeSpy?.mockRestore()
+    cursorToSpy?.mockRestore()
+    clearLineSpy?.mockRestore()
+    clearScreenDownSpy?.mockRestore()
 
     // Restore original properties
     Object.defineProperty(stdout, 'isTTY', {