Simplify to transport-only: remove call protocol, add EventEnvelope, expand stream operators

- Remove src/call.ts (PendingRequestMap, CallEventSchema, CallError) — call protocol belongs in @alkdev/operations
- Add EventEnvelope type ({ type, id, payload }) as the cross-platform serialization contract
- Simplify createPubSub: replace PubSubPublishArgsByKey tuple model with PubSubEventMap; publish(type, id, payload) and subscribe(type, id) use explicit id for topic scoping
- Update Redis adapter to serialize/deserialize full EventEnvelope
- Expand operators: add take, reduce, toArray, batch, dedupe, window, flat, groupBy, chain, join
- Remove @alkdev/typebox runtime dependency (was only used by call.ts)
- Remove ./call sub-path export from package.json and tsup config
- Update all architecture docs to reflect transport-only scope, add Worker adapter, remove call protocol references
- Remove docs/architecture/call-protocol.md
- Update AGENTS.md with new source layout and transport-only principle

src/event-target-redis.ts

@@ -28,10 +28,11 @@
  * - Uses our TypedEventTarget/TypedEvent types from types.ts
  * - Removed tslib dependency
  * - Uses ioredis types directly (already a dependency)
+ * - Serializes full EventEnvelope for cross-process transport
  */
 
 import type { Cluster, Redis } from "ioredis";
-import type { TypedEventTarget, TypedEvent } from "./types.js";
+import type { TypedEventTarget, TypedEvent, EventEnvelope } from "./types.js";
 
 export type CreateRedisEventTargetArgs = {
   publishClient: Redis | Cluster;
@@ -57,8 +58,9 @@ export function createRedisEventTarget<TEvent extends TypedEvent>(
       return;
     }
 
+    const envelope = serializer.parse(message) as EventEnvelope;
     const event = new CustomEvent(channel, {
-      detail: message === "" ? null : serializer.parse(message),
+      detail: envelope,
     }) as TEvent;
     for (const callback of callbacks) {
       callback(event);
@@ -102,7 +104,7 @@ export function createRedisEventTarget<TEvent extends TypedEvent>(
     dispatchEvent(event: TEvent) {
       publishClient.publish(
         event.type,
-        event.detail === undefined ? "" : serializer.stringify(event.detail),
+        serializer.stringify(event.detail),
       );
       return true;
     },