refactor: split stackTrace test and fix mock to store constructor params

Split '0-based line' test into separate location and stackTrace tests.
Fix FakeTestMessageStackFrame to store label, uri, position so
stackTrace assertions can verify 0-based line numbers.

Author: recca0120

packages/extension/__mocks__/vscode.ts

@@ -462,7 +462,16 @@ class FakeEventEmitter<T = void> {
 }
 const EventEmitter = FakeEventEmitter;
 
-class FakeTestMessageStackFrame {}
+class FakeTestMessageStackFrame {
+    label: string;
+    uri?: any;
+    position?: any;
+    constructor(label: string, uri?: any, position?: any) {
+        this.label = label;
+        this.uri = uri;
+        this.position = position;
+    }
+}
 const TestMessageStackFrame = FakeTestMessageStackFrame;
 
 const extensions = {

packages/extension/src/Observers/TestResultObserver.test.ts

@@ -141,7 +141,7 @@ describe('TestResultObserver', () => {
         expect(testRun.passed).toHaveBeenCalledWith(testItem, 42);
     });
 
-    it('should use 0-based line in stackTrace position', () => {
+    it('should use 0-based line in message location', () => {
         observer.testFailed(
             createTestFailed({
                 details: [
@@ -154,11 +154,24 @@ describe('TestResultObserver', () => {
         const failedCall = (testRun.failed as ReturnType<typeof vi.fn>).mock.calls[0];
         const message = failedCall[1];
 
-        // message.location line should be 0-based (10 - 1 = 9)
         expect(message.location.range.start.line).toBe(9);
+    });
 
-        // stackTrace line should also be 0-based (20 - 1 = 19)
-        expect(testRun.failed).toHaveBeenCalled();
+    it('should use 0-based line in stackTrace position', () => {
+        observer.testFailed(
+            createTestFailed({
+                details: [
+                    { file: '/project/tests/ExampleTest.php', line: 10 },
+                    { file: '/project/tests/ExampleTest.php', line: 20 },
+                ],
+            }),
+        );
+
+        const failedCall = (testRun.failed as ReturnType<typeof vi.fn>).mock.calls[0];
+        const message = failedCall[1];
+
+        expect(message.stackTrace).toHaveLength(1);
+        expect(message.stackTrace[0].position.line).toBe(19);
     });
 
     it('should not set location when result.file is undefined', () => {