fix(ci): trace test runner memory retention

test/scripts/test-parallel.test.ts

@@ -1,4 +1,5 @@
 import { describe, expect, it } from "vitest";
+import { parseCompletedTestFileLines } from "../../scripts/test-parallel-memory.mjs";
 import {
   appendCapturedOutput,
   hasFatalTestRunOutput,
@@ -44,3 +45,35 @@ describe("scripts/test-parallel fatal output guard", () => {
     expect(appendCapturedOutput(output, "defg", 5)).toBe("cdefg");
   });
 });
+
+describe("scripts/test-parallel memory trace parsing", () => {
+  it("extracts completed test file lines from colored Vitest output", () => {
+    const output = [
+      "\u001B[32m✓\u001B[39m src/config/doc-baseline.test.ts \u001B[2m(\u001B[22m\u001B[2m8 tests\u001B[22m\u001B[2m)\u001B[22m\u001B[33m 46424\u001B[2mms\u001B[22m\u001B[39m",
+      " \u001B[32m✓\u001B[39m src/infra/restart.test.ts (5 tests) 4.2s",
+    ].join("\n");
+
+    expect(parseCompletedTestFileLines(output)).toEqual([
+      {
+        file: "src/config/doc-baseline.test.ts",
+        durationMs: 46_424,
+      },
+      {
+        file: "src/infra/restart.test.ts",
+        durationMs: 4_200,
+      },
+    ]);
+  });
+
+  it("ignores non-file summary lines", () => {
+    expect(
+      parseCompletedTestFileLines(
+        [
+          " Test Files  2 passed (2)",
+          "      Tests  30 passed (30)",
+          "[test-parallel] done unit code=0 elapsed=68.8s",
+        ].join("\n"),
+      ),
+    ).toEqual([]);
+  });
+});