fix(slack-search): stream task progress in plan mode (#8219)

* fix(slack-search): stream task progress in plan mode

* test(search): await async source integration selection

Author: TheodoreSpeaks

apps/sim/lib/slack-search/assistant-stream.test.ts

@@ -205,6 +205,7 @@ describe('Slack lazy stream lifecycle', () => {
     expect(api.start).not.toHaveBeenCalled()
     await stream.onEvent(toolCall())
     expect(api.start).toHaveBeenCalledOnce()
+    expect(api.start.mock.calls[0][3]).toBe('plan')
     expect(api.start.mock.calls[0][2]).toEqual([
       { type: 'markdown_text', text: '\n' },
       { type: 'markdown_text', text: '\n\n' },
@@ -895,7 +896,7 @@ describe('Slack Assistant delivery', () => {
       'Connect here '
     )
   })
-  it('streams only main public answer text and preserves the original thread', async () => {
+  it('streams only main public answer text in plan mode and preserves the original thread', async () => {
     const { stream } = setup()
     await stream.start()
     await stream.onEvent({
@@ -908,7 +909,7 @@ describe('Slack Assistant delivery', () => {
       'test-token',
       { channel: 'D1', threadTs: '1.1' },
       [{ type: 'markdown_text', text: 'Hello world. ' }],
-      'timeline',
+      'plan',
       expect.any(AbortSignal)
     )
     expect(deliveredText()).toBe('Hello world. ')

apps/sim/lib/slack-search/assistant-stream.ts

@@ -246,7 +246,7 @@ export class SlackSearchAssistantStream {
       }
     }
     this.toolProgress.set(payload.toolCallId, { toolName: payload.toolName, chunk })
-    /** Updating an existing task does not introduce a new position in Slack's timeline. */
+    /** Existing task updates can be delivered without waiting for preceding answer text. */
     this.pendingProgress.push({ textEnd: payload.phase === 'call' ? this.text.length : 0, chunk })
   }
 
@@ -356,7 +356,7 @@ export class SlackSearchAssistantStream {
       token,
       { channel, threadTs },
       [...this.leadingChunks, chunk],
-      'timeline',
+      'plan',
       signal
     )
     this.leadingChunks = []