test: 添加 json/truncate/path/tokens 模块测试

- json.test.ts: 27 tests (safeParseJSON, safeParseJSONC, parseJSONL, addItemToJSONCArray)
- truncate.test.ts: 24 tests (truncateToWidth, truncateStartToWidth, truncatePathMiddle, truncate, wrapText)
- path.test.ts: 15 tests (containsPathTraversal, normalizePathForConfigKey)
- tokens.test.ts: 22 tests (getTokenCountFromUsage, getTokenUsage, tokenCountFromLastAPIResponse, etc.)

使用 mock.module() 切断 log.ts/tokenEstimation.ts/slowOperations.ts 重依赖链

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

src/utils/__tests__/path.test.ts

@@ -0,0 +1,72 @@
+import { describe, expect, test } from "bun:test";
+import { containsPathTraversal, normalizePathForConfigKey } from "../path";
+
+// ─── containsPathTraversal ──────────────────────────────────────────────
+
+describe("containsPathTraversal", () => {
+  test("detects ../ at start", () => {
+    expect(containsPathTraversal("../foo")).toBe(true);
+  });
+
+  test("detects ../ in middle", () => {
+    expect(containsPathTraversal("foo/../bar")).toBe(true);
+  });
+
+  test("detects .. at end", () => {
+    expect(containsPathTraversal("foo/..")).toBe(true);
+  });
+
+  test("detects standalone ..", () => {
+    expect(containsPathTraversal("..")).toBe(true);
+  });
+
+  test("detects backslash traversal", () => {
+    expect(containsPathTraversal("foo\\..\\bar")).toBe(true);
+  });
+
+  test("returns false for normal path", () => {
+    expect(containsPathTraversal("foo/bar/baz")).toBe(false);
+  });
+
+  test("returns false for single dot", () => {
+    expect(containsPathTraversal("./foo")).toBe(false);
+  });
+
+  test("returns false for ... in filename", () => {
+    expect(containsPathTraversal("foo/...bar")).toBe(false);
+  });
+
+  test("returns false for empty string", () => {
+    expect(containsPathTraversal("")).toBe(false);
+  });
+
+  test("returns false for dotdot in filename without separator", () => {
+    expect(containsPathTraversal("foo..bar")).toBe(false);
+  });
+});
+
+// ─── normalizePathForConfigKey ──────────────────────────────────────────
+
+describe("normalizePathForConfigKey", () => {
+  test("normalizes forward slashes (no change on POSIX)", () => {
+    expect(normalizePathForConfigKey("foo/bar/baz")).toBe("foo/bar/baz");
+  });
+
+  test("resolves dot segments", () => {
+    expect(normalizePathForConfigKey("foo/./bar")).toBe("foo/bar");
+  });
+
+  test("resolves double-dot segments", () => {
+    expect(normalizePathForConfigKey("foo/bar/../baz")).toBe("foo/baz");
+  });
+
+  test("handles absolute path", () => {
+    const result = normalizePathForConfigKey("/Users/test/project");
+    expect(result).toBe("/Users/test/project");
+  });
+
+  test("converts backslashes to forward slashes", () => {
+    const result = normalizePathForConfigKey("foo\\bar\\baz");
+    expect(result).toBe("foo/bar/baz");
+  });
+});