refactor: 统一 log.ts/debug.ts 的测试 mock 为共享定义

- 新增 tests/mocks/log.ts 和 tests/mocks/debug.ts，覆盖源文件全部实际导出
- 移除旧 mock 中不存在的导出（logToFile、logEvent、getLogFilePath）
- 13 个测试文件改为使用共享 mock，避免定义分散和不一致

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

tests/mocks/log.ts

@@ -0,0 +1,24 @@
+/**
+ * Shared mock for src/utils/log.ts
+ *
+ * Cuts the bootstrap/state.ts dependency chain (module-level realpathSync + randomUUID).
+ * Must be called via mock.module("src/utils/log.ts", logMock) BEFORE any import that
+ * transitively depends on log.ts.
+ *
+ * Exported as a factory so each call produces a fresh object (mock.module requirement).
+ */
+export function logMock() {
+  return {
+    logError: () => {},
+    getLogDisplayTitle: () => "",
+    dateToFilename: (d: Date) => d.toISOString().replace(/[:.]/g, "-"),
+    attachErrorLogSink: () => {},
+    getInMemoryErrors: () => [] as Array<{ error: string; timestamp: string }>,
+    loadErrorLogs: async () => [],
+    getErrorLogByIndex: async () => null,
+    logMCPError: () => {},
+    logMCPDebug: () => {},
+    captureAPIRequest: () => {},
+    _resetErrorLogForTesting: () => {},
+  }
+}