test: migrate suites to e2e coverage layout

src/agents/pi-embedded-helpers.iscompactionfailureerror.e2e.test.ts

@@ -0,0 +1,19 @@
+import { describe, expect, it } from "vitest";
+import { isCompactionFailureError } from "./pi-embedded-helpers/errors.js";
+describe("isCompactionFailureError", () => {
+  it("matches compaction overflow failures", () => {
+    const samples = [
+      'Context overflow: Summarization failed: 400 {"message":"prompt is too long"}',
+      "auto-compaction failed due to context overflow",
+      "Compaction failed: prompt is too long",
+      "Summarization failed: context window exceeded for this request",
+    ];
+    for (const sample of samples) {
+      expect(isCompactionFailureError(sample)).toBe(true);
+    }
+  });
+  it("ignores non-compaction overflow errors", () => {
+    expect(isCompactionFailureError("Context overflow: prompt too large")).toBe(false);
+    expect(isCompactionFailureError("rate limit exceeded")).toBe(false);
+  });
+});