chore: import upstream snapshot with attribution

tests/unit/compression/compressionChannel.test.ts

@@ -0,0 +1,42 @@
+import { describe, it } from "node:test";
+import assert from "node:assert/strict";
+
+import {
+  type DashboardChannel,
+  CHANNEL_EVENTS,
+  getChannelForEvent,
+} from "../../../src/lib/events/types.ts";
+
+describe("compression WS channel (U5)", () => {
+  it("DashboardChannel includes 'compression'", () => {
+    // The type must include 'compression' — we verify it at runtime by ensuring
+    // CHANNEL_EVENTS has the key (TypeScript narrows keys to DashboardChannel).
+    const channels = Object.keys(CHANNEL_EVENTS) as DashboardChannel[];
+    assert.ok(
+      channels.includes("compression" as DashboardChannel),
+      "CHANNEL_EVENTS must have a 'compression' key"
+    );
+  });
+
+  it("CHANNEL_EVENTS.compression contains 'compression.completed'", () => {
+    const events = (CHANNEL_EVENTS as Record<string, string[]>)["compression"];
+    assert.ok(Array.isArray(events), "CHANNEL_EVENTS.compression should be an array");
+    assert.ok(
+      events.includes("compression.completed"),
+      "compression channel must list 'compression.completed'"
+    );
+  });
+
+  it("getChannelForEvent maps 'compression.completed' → 'compression'", () => {
+    const channel = getChannelForEvent(
+      "compression.completed" as Parameters<typeof getChannelForEvent>[0]
+    );
+    assert.equal(channel, "compression");
+  });
+
+  it("existing channels still route correctly", () => {
+    assert.equal(getChannelForEvent("request.started"), "requests");
+    assert.equal(getChannelForEvent("combo.target.attempt"), "combo");
+    assert.equal(getChannelForEvent("credential.health.changed"), "credentials");
+  });
+});