perf: gate perf logs and dedup build_config_update on first message (#8627)

Signed-off-by: Bradley Axen <baxen@squareup.com>

ui/goose2/src/shared/api/acp.ts

@@ -6,6 +6,7 @@ import {
   clearActiveMessageId,
 } from "./acpNotificationHandler";
 import { searchSessionsViaExports } from "./sessionSearch";
+import { perfLog } from "@/shared/lib/perfLog";
 
 export interface AcpProvider {
   id: string;
@@ -36,6 +37,8 @@ export async function acpSendMessage(
   options: AcpSendMessageOptions = {},
 ): Promise<void> {
   const { systemPrompt, personaId, images } = options;
+  const sid = sessionId.slice(0, 8);
+  const tStart = performance.now();
 
   const gooseSessionId = sessionTracker.getGooseSessionId(sessionId, personaId);
   if (!gooseSessionId) {
@@ -57,7 +60,15 @@ export async function acpSendMessage(
   const messageId = crypto.randomUUID();
   setActiveMessageId(gooseSessionId, messageId);
 
+  perfLog(
+    `[perf:send] ${sid} acpSendMessage → prompt(len=${prompt.length}, imgs=${images?.length ?? 0})`,
+  );
+  const tPrompt = performance.now();
   await directAcp.prompt(gooseSessionId, content);
+  const tDone = performance.now();
+  perfLog(
+    `[perf:send] ${sid} prompt() resolved in ${(tDone - tPrompt).toFixed(1)}ms (total acpSendMessage ${(tDone - tStart).toFixed(1)}ms)`,
+  );
 
   clearActiveMessageId(gooseSessionId);
 }
@@ -69,12 +80,20 @@ export async function acpPrepareSession(
   workingDir: string,
   options: AcpPrepareSessionOptions = {},
 ): Promise<void> {
+  const sid = sessionId.slice(0, 8);
+  const t0 = performance.now();
+  perfLog(
+    `[perf:prepare] ${sid} acpPrepareSession start (provider=${providerId})`,
+  );
   await sessionTracker.prepareSession(
     sessionId,
     providerId,
     workingDir,
     options.personaId,
   );
+  perfLog(
+    `[perf:prepare] ${sid} acpPrepareSession done in ${(performance.now() - t0).toFixed(1)}ms`,
+  );
 }
 
 export async function acpSetModel(
@@ -125,7 +144,13 @@ export async function acpLoadSession(
   workingDir?: string,
 ): Promise<void> {
   const effectiveWorkingDir = workingDir ?? "~/.goose/artifacts";
+  const sid = sessionId.slice(0, 8);
+  const t0 = performance.now();
+  perfLog(`[perf:load] ${sid} acpLoadSession → client.loadSession`);
   await directAcp.loadSession(gooseSessionId, effectiveWorkingDir);
+  perfLog(
+    `[perf:load] ${sid} client.loadSession resolved in ${(performance.now() - t0).toFixed(1)}ms`,
+  );
   sessionTracker.registerSession(
     sessionId,
     gooseSessionId,