refactor(core): make v2 session inputs event sourced (#30785)

packages/opencode/src/session/prompt.ts

@@ -51,6 +51,7 @@ import { RuntimeFlags } from "@/effect/runtime-flags"
 import { EventV2Bridge } from "@/event-v2-bridge"
 import { Database } from "@opencode-ai/core/database/database"
 import { SessionEvent } from "@opencode-ai/core/session/event"
+import { SessionMessage } from "@opencode-ai/core/session/message"
 import { ModelV2 } from "@opencode-ai/core/model"
 import { ProviderV2 } from "@opencode-ai/core/provider"
 import { AgentAttachment, FileAttachment, Prompt, ReferenceAttachment, Source } from "@opencode-ai/core/session/prompt"
@@ -563,6 +564,7 @@ export const layer = Layer.effect(
             if (flags.experimentalEventSystem) {
               yield* events.publish(SessionEvent.Shell.Started, {
                 sessionID: input.sessionID,
+                messageID: SessionMessage.ID.create(),
                 timestamp: DateTime.makeUnsafe(started),
                 callID: part.callID,
                 command: input.command,
@@ -738,6 +740,7 @@ export const layer = Layer.effect(
       if (current?.agent !== info.agent) {
         yield* events.publish(SessionEvent.AgentSwitched, {
           sessionID: input.sessionID,
+          messageID: SessionMessage.ID.create(),
           timestamp: DateTime.makeUnsafe(info.time.created),
           agent: info.agent,
         })
@@ -749,6 +752,7 @@ export const layer = Layer.effect(
       ) {
         yield* events.publish(SessionEvent.ModelSwitched, {
           sessionID: input.sessionID,
+          messageID: SessionMessage.ID.create(),
           timestamp: DateTime.makeUnsafe(info.time.created),
           model: {
             id: ModelV2.ID.make(info.model.modelID),
@@ -1190,6 +1194,7 @@ export const layer = Layer.effect(
       if (flags.experimentalEventSystem) {
         yield* events.publish(SessionEvent.Prompted, {
           sessionID: input.sessionID,
+          messageID: SessionMessage.ID.create(),
           timestamp: DateTime.makeUnsafe(info.time.created),
           delivery: "steer",
           prompt: new Prompt({
@@ -1205,6 +1210,7 @@ export const layer = Layer.effect(
         if (flags.experimentalEventSystem) {
           yield* events.publish(SessionEvent.Synthetic, {
             sessionID: input.sessionID,
+            messageID: SessionMessage.ID.create(),
             timestamp: DateTime.makeUnsafe(info.time.created),
             text,
           })