test: prove TechLog UI migration parity

tests/unit/bounded-body-reader.test.ts

@@ -121,6 +121,29 @@ describe("bounded body reader", () => {
     });
   });
 
+  it("abandons and cancels a bounded read when its lifetime aborts", async () => {
+    const controller = new AbortController();
+    const reader = {
+      read: vi.fn(() => new Promise<never>(() => {})),
+      cancel: vi.fn().mockRejectedValue(new Error("abandoned cancel failed")),
+      releaseLock: vi.fn(),
+    };
+    const response = {
+      headers: new Headers(),
+      body: { getReader: () => reader },
+    } as unknown as Response;
+
+    const outcome = readBoundedBytes(response, 3, controller.signal);
+    controller.abort();
+
+    await expect(outcome).resolves.toEqual({
+      ok: false,
+      code: "RESPONSE_STREAM_FAILURE",
+    });
+    expect(reader.cancel).toHaveBeenCalledOnce();
+    expect(reader.releaseLock).toHaveBeenCalledOnce();
+  });
+
   it("detects a forbidden body from declared length without reading it", async () => {
     const cancel = vi.fn();
     const response = {
@@ -200,6 +223,29 @@ describe("bounded body reader", () => {
     });
   });
 
+  it("abandons and cancels a forbidden-body probe when its lifetime aborts", async () => {
+    const controller = new AbortController();
+    const reader = {
+      read: vi.fn(() => new Promise<never>(() => {})),
+      cancel: vi.fn().mockRejectedValue(new Error("abandoned cancel failed")),
+      releaseLock: vi.fn(),
+    };
+    const response = {
+      headers: new Headers(),
+      body: { getReader: () => reader },
+    } as unknown as Response;
+
+    const outcome = probeForbiddenBody(response, controller.signal);
+    controller.abort();
+
+    await expect(outcome).resolves.toEqual({
+      ok: false,
+      code: "RESPONSE_STREAM_FAILURE",
+    });
+    expect(reader.cancel).toHaveBeenCalledOnce();
+    expect(reader.releaseLock).toHaveBeenCalledOnce();
+  });
+
   it("decodes valid JSON and distinguishes UTF-8 from JSON failures", () => {
     expect(decodeJsonBytes(new TextEncoder().encode('{"ok":true}'))).toEqual({
       ok: true,