fix(webapp): use getRequestAbortSignal() for dashboard stream routes

Three dashboard-scoped stream routes were passing request.signal into
realtimeStream.streamResponse. That signal is broken under
Remix+Express (see apps/webapp/CLAUDE.md, nodejs/node#55428 — the chain
is severed when Remix internally clones the Request), so when a user
closes their dashboard tab the signal never fires. The underlying
RedisRealtimeStreams.streamResponse loops while(!signal.aborted) over
XREAD BLOCK and only exits on its 15s inactivity timeout; the S2 path
keeps the upstream fetch open for up to its 60s wait window.

Thread getRequestAbortSignal() through:
  - resources/orgs/.../runs/$runParam/realtime/v1/streams/$runId/$streamId
  - resources/orgs/.../runs/$runParam/realtime/v1/streams/$runId/input/$streamId
  - resources/orgs/.../playground/realtime/v1/streams/$runId/$streamId
Each picks up the Express res.on('close')-backed signal that fires
reliably when the downstream client disconnects.

Author: ericallam

apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.playground.realtime.v1.streams.$runId.$streamId.ts

@@ -1,6 +1,7 @@
 import { type LoaderFunctionArgs } from "@remix-run/server-runtime";
 import { z } from "zod";
 import { $replica } from "~/db.server";
+import { getRequestAbortSignal } from "~/services/httpAsyncStorage.server";
 import { getRealtimeStreamInstance } from "~/services/realtime/v1StreamsGlobal.server";
 import { findProjectBySlug } from "~/models/project.server";
 import { findEnvironmentBySlug } from "~/models/runtimeEnvironment.server";
@@ -54,8 +55,16 @@ export async function loader({ request, params }: LoaderFunctionArgs) {
 
   const realtimeStream = getRealtimeStreamInstance(environment, run.realtimeStreamsVersion);
 
-  return realtimeStream.streamResponse(request, run.friendlyId, streamId, request.signal, {
-    lastEventId,
-    timeoutInSeconds,
-  });
+  // `request.signal` is severed by Remix's Request.clone() + Node undici GC bug
+  // (see apps/webapp/CLAUDE.md). Use the Express res.on('close')-backed signal.
+  return realtimeStream.streamResponse(
+    request,
+    run.friendlyId,
+    streamId,
+    getRequestAbortSignal(),
+    {
+      lastEventId,
+      timeoutInSeconds,
+    }
+  );
 }

apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.runs.$runParam.realtime.v1.streams.$runId.$streamId.ts

@@ -1,6 +1,7 @@
 import { type LoaderFunctionArgs } from "@remix-run/server-runtime";
 import { z } from "zod";
 import { $replica } from "~/db.server";
+import { getRequestAbortSignal } from "~/services/httpAsyncStorage.server";
 import { getRealtimeStreamInstance } from "~/services/realtime/v1StreamsGlobal.server";
 import { findProjectBySlug } from "~/models/project.server";
 import { findEnvironmentBySlug } from "~/models/runtimeEnvironment.server";
@@ -72,8 +73,17 @@ export async function loader({ request, params }: LoaderFunctionArgs) {
 
   const realtimeStream = getRealtimeStreamInstance(environment, run.realtimeStreamsVersion);
 
-  return realtimeStream.streamResponse(request, run.friendlyId, streamId, request.signal, {
-    lastEventId,
-    timeoutInSeconds,
-  });
+  // `request.signal` is severed by Remix's Request.clone() + Node undici GC bug
+  // (see apps/webapp/CLAUDE.md). Use the Express res.on('close')-backed signal so
+  // the upstream stream fetch actually aborts when the user closes the tab.
+  return realtimeStream.streamResponse(
+    request,
+    run.friendlyId,
+    streamId,
+    getRequestAbortSignal(),
+    {
+      lastEventId,
+      timeoutInSeconds,
+    }
+  );
 }

apps/webapp/app/routes/resources.orgs.$organizationSlug.projects.$projectParam.env.$envParam.runs.$runParam.realtime.v1.streams.$runId.input.$streamId.ts

@@ -1,6 +1,7 @@
 import { type LoaderFunctionArgs } from "@remix-run/server-runtime";
 import { z } from "zod";
 import { $replica } from "~/db.server";
+import { getRequestAbortSignal } from "~/services/httpAsyncStorage.server";
 import { getRealtimeStreamInstance } from "~/services/realtime/v1StreamsGlobal.server";
 import { findProjectBySlug } from "~/models/project.server";
 import { findEnvironmentBySlug } from "~/models/runtimeEnvironment.server";
@@ -74,11 +75,13 @@ export async function loader({ request, params }: LoaderFunctionArgs) {
 
   const realtimeStream = getRealtimeStreamInstance(environment, run.realtimeStreamsVersion);
 
+  // `request.signal` is severed by Remix's Request.clone() + Node undici GC bug
+  // (see apps/webapp/CLAUDE.md). Use the Express res.on('close')-backed signal.
   return realtimeStream.streamResponse(
     request,
     run.friendlyId,
     `$trigger.input:${streamId}`,
-    request.signal,
+    getRequestAbortSignal(),
     {
       lastEventId,
       timeoutInSeconds,