Improve v2 session message rendering (#25634)

packages/opencode/src/session/prompt.ts

@@ -56,6 +56,7 @@ import { SessionRunState } from "./run-state"
 import { EffectBridge } from "@/effect/bridge"
 import { EventV2 } from "@/v2/event"
 import { SessionEvent } from "@/v2/session-event"
+import { Modelv2 } from "@/v2/model"
 import { AgentAttachment, FileAttachment, Source } from "@/v2/session-prompt"
 import * as DateTime from "effect/DateTime"
 import { eq } from "@/storage/db"
@@ -978,9 +979,11 @@ NOTE: At any point in time through this workflow you should feel free to ask the
         EventV2.run(SessionEvent.ModelSwitched.Sync, {
           sessionID: input.sessionID,
           timestamp: DateTime.makeUnsafe(info.time.created),
-          id: info.model.modelID,
-          providerID: info.model.providerID,
-          variant: info.model.variant,
+          model: {
+            id: Modelv2.ID.make(info.model.modelID),
+            providerID: Modelv2.ProviderID.make(info.model.providerID),
+            variant: Modelv2.VariantID.make(info.model.variant ?? "default"),
+          },
         })
       }