fix(core): preserve event routing semantics

packages/protocol/test/event.test.ts

@@ -0,0 +1,27 @@
+import { describe, expect, test } from "bun:test"
+import { Event } from "@opencode-ai/schema/event"
+import { Schema } from "effect"
+import { EventSchema } from "../src/groups/event"
+
+describe("EventSchema", () => {
+  test("requires durable metadata on durable events", () => {
+    expect(
+      Schema.is(EventSchema)({
+        id: Event.ID.create(),
+        type: "session.created",
+        data: { sessionID: "session" },
+      }),
+    ).toBe(false)
+  })
+
+  test("rejects durable metadata on live events", () => {
+    expect(
+      Schema.is(EventSchema)({
+        id: Event.ID.create(),
+        type: "server.connected",
+        durable: { aggregateID: "aggregate", seq: 0, version: 1 },
+        data: {},
+      }),
+    ).toBe(false)
+  })
+})