fix(tests): stub getAutoSessionTokenForModel and guard logCopilotRateLimits

- Guard logCopilotRateLimits against null/undefined headers to prevent
  TypeError when test mocks omit the headers property
- Stub getAutoSessionTokenForModel in create-chat-completions and
  create-responses tests to prevent unintended /models/session fetch
  that was offsetting fetchMock.mock.calls[] indices and causing
  response.json/text method-missing failures

Co-Authored-By: Claude Sonnet 4 <noreply@anthropic.com>

Author: cuipengfei

src/lib/copilot-rate-limit.ts

@@ -77,7 +77,10 @@ export const getCopilotRateLimitUsage = (
   }
 }
 
-export const logCopilotRateLimits = (headers: HeadersLike): void => {
+export const logCopilotRateLimits = (
+  headers: HeadersLike | null | undefined,
+): void => {
+  if (!headers) return
   for (const type of copilotRateLimitTypes) {
     const usage = getCopilotRateLimitUsage(headers, type)
 

tests/create-chat-completions.test.ts

@@ -10,6 +10,7 @@ import {
 
 import type { ChatCompletionsPayload } from "../src/services/copilot/create-chat-completions"
 
+import * as autoSession from "../src/lib/auto-session"
 import { getAttachedResponseHeaders } from "../src/lib/response-headers"
 import { state } from "../src/lib/state"
 import { createChatCompletions } from "../src/services/copilot/create-chat-completions"
@@ -69,6 +70,9 @@ describe("Interaction headers", () => {
     trackPanelRequestCalls = 0
     trackGhostTextShownCalls = 0
 
+    spyOn(autoSession, "getAutoSessionTokenForModel").mockResolvedValue(
+      "test-session-token",
+    )
     spyOn(telemetryModule, "trackRequestSent").mockImplementation(() => {})
     spyOn(telemetryModule, "trackResponseSuccess").mockImplementation(() => {})
     spyOn(telemetryModule, "trackResponseError").mockImplementation(() => {})
@@ -246,6 +250,9 @@ describe("modelCallId telemetry alignment", () => {
     state.interactionId = "test-interaction-id"
     state.forceAgent = false
 
+    spyOn(autoSession, "getAutoSessionTokenForModel").mockResolvedValue(
+      "test-session-token",
+    )
     spyOn(telemetryModule, "trackRequestSent").mockImplementation(
       (...args: Parameters<typeof telemetryModule.trackRequestSent>) => {
         capturedModelCallIdFromRequestSent = args[3]
@@ -439,6 +446,9 @@ describe("Initiator detection (last-message role)", () => {
     state.interactionId = "test-interaction-id"
     state.forceAgent = false
 
+    spyOn(autoSession, "getAutoSessionTokenForModel").mockResolvedValue(
+      "test-session-token",
+    )
     spyOn(telemetryModule, "trackRequestSent").mockImplementation(() => {})
     spyOn(telemetryModule, "trackResponseSuccess").mockImplementation(() => {})
     spyOn(telemetryModule, "trackResponseError").mockImplementation(() => {})

tests/create-responses.test.ts

@@ -9,6 +9,7 @@ import {
   describe,
 } from "bun:test"
 
+import * as autoSession from "../src/lib/auto-session"
 import { getAttachedPremiumInfo } from "../src/lib/logger"
 import { getAttachedResponseHeaders } from "../src/lib/response-headers"
 import { state } from "../src/lib/state"
@@ -98,6 +99,10 @@ beforeEach(() => {
   // @ts-expect-error - Mock fetch doesn't implement all fetch properties
   ;(globalThis as unknown as { fetch: typeof fetch }).fetch = fetchMock
 
+  spyOn(autoSession, "getAutoSessionTokenForModel").mockResolvedValue(
+    "test-session-token",
+  )
+
   // Capture modelCallId using spyOn (can be restored by mock.restore())
   spyOn(telemetryModule, "trackRequestSent").mockImplementation(
     (