refactor(copilot): drop unused steering billing metadata

Author: icecrasher321

apps/sim/app/api/billing/update-cost/route.ts

@@ -229,11 +229,9 @@ async function updateCostInner(req: NextRequest, span: Span): Promise<NextRespon
 
     let billingAttribution = suppliedBillingAttribution
     /**
-     * Old Go creates its random idempotency key after admission and returns no
-     * protocol or payer envelope. The markerless legacy-v0 path therefore
-     * re-resolves a locally known workspace at callback time. This mutable
-     * compatibility semantic is intentionally unreachable from modern
-     * attributed-v1/direct-v1 callbacks.
+     * Local self-hosted markerless callbacks have no immutable payer envelope,
+     * so they re-resolve a locally known workspace at callback time. Hosted
+     * attributed-v1/direct-v1 callbacks can never reach this mutable path.
      */
     if (isMarkerlessLegacy && workspaceId) {
       billingAttribution =

apps/sim/app/api/copilot/chat/steer/route.ts

@@ -73,7 +73,6 @@ export const POST = withRouteHandler((request: NextRequest) =>
           chatId,
           steeringId,
           content,
-          workspaceId: run?.workspaceId ?? undefined,
         })
         queued = result.queued
         goStatus = result.status

apps/sim/lib/copilot/request/session/steer.ts

@@ -1,8 +1,4 @@
 import type { Context } from '@opentelemetry/api'
-import {
-  COPILOT_BILLING_PROTOCOL,
-  COPILOT_BILLING_PROTOCOL_HEADER,
-} from '@/lib/billing/core/billing-attribution'
 import { TraceAttr } from '@/lib/copilot/generated/trace-attributes-v1'
 import { fetchGo } from '@/lib/copilot/request/go/fetch'
 import { getMothershipBaseURL, getMothershipSourceEnvHeaders } from '@/lib/copilot/server/agent-url'
@@ -25,7 +21,6 @@ export async function requestStreamSteering(params: {
   chatId: string
   steeringId: string
   content: string
-  workspaceId?: string
   timeoutMs?: number
   otelContext?: Context
 }): Promise<{ queued: boolean; status: number }> {
@@ -41,7 +36,6 @@ export async function requestStreamSteering(params: {
 
   const headers: Record<string, string> = {
     'Content-Type': 'application/json',
-    [COPILOT_BILLING_PROTOCOL_HEADER]: COPILOT_BILLING_PROTOCOL.legacy,
   }
   if (env.COPILOT_API_KEY) {
     headers['x-api-key'] = env.COPILOT_API_KEY