feat(client-runtime): add target-owned conversation snapshots

packages/client/runtime/tests/client-apply.spec.ts

@@ -126,6 +126,7 @@ describe('runtime client apply', () => {
     const rebuild = vi.spyOn(Session.prototype, 'rebuildConversationRegistry')
     const definition: ConversationNodeDefinition<null> = {
       kind: 'registry-probe',
+      target: 'chat',
       match: () => null,
       start: () => null,
       update: context => context.state,

packages/client/runtime/tests/conversation-assembler.spec.ts

@@ -30,10 +30,16 @@ interface TestSnapshot {
 }
 
 class TestEventDefinitions {
+  readonly definitions: readonly ConversationNodeDefinition[]
+  readonly fallback: ConversationNodeDefinition | undefined
+
   constructor(
-    readonly definitions: readonly ConversationNodeDefinition[],
-    readonly fallback?: ConversationNodeDefinition,
-  ) {}
+    definitions: readonly ConversationNodeDefinition[],
+    fallback?: ConversationNodeDefinition,
+  ) {
+    this.definitions = definitions.map(asChatDefinition)
+    this.fallback = fallback === undefined ? undefined : asChatDefinition(fallback)
+  }
 
   entries(): readonly ConversationNodeDefinition[] {
     return this.definitions
@@ -44,6 +50,12 @@ class TestEventDefinitions {
   }
 }
 
+function asChatDefinition(definition: ConversationNodeDefinition): ConversationNodeDefinition {
+  return definition.buildViewNode === undefined || definition.target !== undefined
+    ? definition
+    : { ...definition, target: 'chat' }
+}
+
 class TestViewDefinitions {
   constructor(readonly definitions: readonly ConversationViewDefinition[]) {}
 
@@ -93,7 +105,10 @@ function chatSnapshot(assembler: ConversationNodeAssembler): TestSnapshot | unde
   return assembler.snapshot('chat') as TestSnapshot | undefined
 }
 
-function node(context: Parameters<ConversationNodeDefinition['buildViewNode']>[0], data: unknown): ConversationViewNode {
+function node(
+  context: Parameters<NonNullable<ConversationNodeDefinition['buildViewNode']>>[0],
+  data: unknown,
+): ConversationViewNode {
   return {
     key: context.key,
     kind: context.kind,

packages/client/runtime/tests/conversation-registry.spec.ts

@@ -13,6 +13,7 @@ import { FakeApiClient, ok } from './fake-api.ts'
 function eventDefinition(kind: string): ConversationNodeDefinition<null> {
   return {
     kind,
+    target: 'chat',
     match: () => null,
     start: () => null,
     update: context => context.state,

packages/client/runtime/tests/session.spec.ts

@@ -123,12 +123,13 @@ function testViewDefinition(): ConversationViewDefinition<ChatConversationViewNo
 
 const TEST_EVENT_DEFINITION: ConversationNodeDefinition<TestEventState> = {
   kind: 'runtime-test-event',
+  target: 'chat',
   match: event => ({ id: String(event.seq), role: 'start' }),
   start: (_context, match) => ({ event: match.event, view: match.view }),
   update: context => context.state,
   publication: match => match.event.type === 'assistant/chunk' ? 'animation-frame' : 'immediate',
-  buildViewNode: (context, target) => {
-    if (target !== 'chat' || context.state === undefined || context.start === undefined) return null
+  buildViewNode: (context) => {
+    if (context.state === undefined || context.start === undefined) return null
     return {
       key: context.key,
       kind: 'runtime-test-event',