fix(app): make session navigation stable and fast (#33569)

Co-authored-by: Brendan Allan <git@brendonovich.dev>

packages/app/e2e/performance/timeline/timeline-test-helpers.ts

@@ -1,7 +1,7 @@
 import type { Page } from "@playwright/test"
 import { base64Encode } from "@opencode-ai/core/util/encode"
 import { mockOpenCodeServer } from "../../utils/mock-server"
-import { fixture } from "./session-timeline-stress.fixture"
+import { fixture, pageMessages } from "./session-timeline-stress.fixture"
 
 export async function installTimelineSettings(page: Page) {
   await page.addInitScript(() => {
@@ -9,6 +9,7 @@ export async function installTimelineSettings(page: Page) {
       "settings.v3",
       JSON.stringify({
         general: {
+          newLayoutDesigns: true,
           editToolPartsExpanded: true,
           shellToolPartsExpanded: true,
           showReasoningSummaries: true,
@@ -19,20 +20,24 @@ export async function installTimelineSettings(page: Page) {
   })
 }
 
-export function mockStressTimeline(page: Page) {
+export function mockStressTimeline(
+  page: Page,
+  input?: { onMessages?: (input: { sessionID: string; before?: string; phase: "start" | "end" }) => void },
+) {
   return mockOpenCodeServer(page, {
     sessions: fixture.sessions,
     provider: fixture.provider,
     directory: fixture.directory,
     project: fixture.project,
-    pageMessages: (sessionID) => ({ items: fixture.messages[sessionID as keyof typeof fixture.messages] ?? [] }),
+    pageMessages,
+    onMessages: input?.onMessages,
   })
 }
 
-export async function installStressSessionTabs(page: Page) {
-  const server = `http://${process.env.PLAYWRIGHT_SERVER_HOST ?? "127.0.0.1"}:${process.env.PLAYWRIGHT_SERVER_PORT ?? "4096"}`
+export async function installStressSessionTabs(page: Page, input?: { draftID?: string; sessionIDs?: string[] }) {
+  const server = stressServer()
   await page.addInitScript(
-    ({ directory, sourceID, targetID, dirBase64, server }) => {
+    ({ directory, sessionIDs, dirBase64, server, draftID }) => {
       localStorage.setItem(
         "opencode.global.dat:server",
         JSON.stringify({
@@ -43,25 +48,36 @@ export async function installStressSessionTabs(page: Page) {
       localStorage.setItem(
         "opencode.global.dat:tabs",
         JSON.stringify(
-          [sourceID, targetID].map((sessionId) => ({
-            type: "session",
-            server,
-            dirBase64,
-            sessionId,
-          })),
+          [
+            ...sessionIDs.map((sessionId) => ({
+              type: "session",
+              server,
+              dirBase64,
+              sessionId,
+            })),
+            ...(draftID ? [{ type: "draft", draftID, server, directory }] : []),
+          ],
         ),
       )
     },
     {
       directory: fixture.directory,
-      sourceID: fixture.sourceID,
-      targetID: fixture.targetID,
+      sessionIDs: input?.sessionIDs ?? [fixture.sourceID, fixture.targetID],
       dirBase64: base64Encode(fixture.directory),
       server,
+      draftID: input?.draftID,
     },
   )
 }
 
 export function stressSessionHref(sessionID: string) {
-  return `/${base64Encode(fixture.directory)}/session/${sessionID}`
+  return `/server/${base64Encode(stressServer())}/session/${sessionID}`
+}
+
+export function stressDraftHref(draftID: string) {
+  return `/new-session?draftId=${encodeURIComponent(draftID)}`
+}
+
+function stressServer() {
+  return `http://${process.env.PLAYWRIGHT_SERVER_HOST ?? "127.0.0.1"}:${process.env.PLAYWRIGHT_SERVER_PORT ?? "4096"}`
 }