fix: preserve conversation settings for models and scheduled messages

Preserve explicit Runtime model selections and Harness configuration rules without pinning resolved defaults. Expose fixed Runtime models in project settings and keep SSH conversations inheriting their project selection.

Dispatch scheduled instructions through ordinary conversation requests using current history, Runtime, work mode, and knowledge scope. Persist conversation work modes and update scheduling documentation and regression tests.

Validation checkpoint: typecheck, lint, and 104 focused tests passed. The SSH inheritance regression passed in isolation, but its process timed out on exit. Full-suite completion, remaining model documentation review, and real end-to-end validation are still pending.

Release note: Preserve fixed model choices and let scheduled messages use their conversation's current settings and history.

src/main/assistant/assistant-database.test.ts

@@ -131,6 +131,80 @@ function claimManualScheduleQueueItem(
 }
 
 describe('AssistantDatabase', () => {
+  it('keeps timed messages independent of creation-time execution settings', async () => {
+    const database = await createDatabase()
+    const project = database.createProject({
+      name: 'Scheduled project', rootPath: 'C:\\Workspace', description: '',
+      defaultWorkMode: 'execute', runtimeSelection: { provider: 'opencode' }
+    })
+    const schedule = database.createSchedule({
+      projectId: project.id, title: 'Timed message', prompt: 'Continue our work',
+      recurrence: 'daily', nextRunAt: '2026-09-10T00:00:00Z'
+    })
+    expect(schedule.runtimeSelection).toBeUndefined()
+    const conversation = database.getConversation(schedule.conversationId)
+    expect(conversation.runtimeSelection).toBeUndefined()
+    expect(conversation.workMode).toBeUndefined()
+    const { messages, ...header } = conversation
+    database.saveLocalConversations([{ header: {
+      ...header, workMode: 'execute',
+      runtimeSelection: { provider: 'continue' }
+    }, messages }])
+    const existing = database.createSchedule({
+      projectId: project.id, conversationId: conversation.id,
+      title: 'Second message', prompt: 'Continue', workMode: 'ask',
+      recurrence: 'once', nextRunAt: '2026-09-11T00:00:00Z'
+    })
+    expect(existing.runtimeSelection).toBeUndefined()
+    database.close()
+    database.initialize('C:\\Workspace')
+    expect(database.getConversation(conversation.id)).toMatchObject({
+      workMode: 'execute', runtimeSelection: { provider: 'continue' }
+    })
+    database.close()
+  })
+
+  it('releases scheduled dispatches for retry and completes accepted ordinary runs without replay on restart', async () => {
+    const database = await createDatabase()
+    const schedule = database.createSchedule({
+      title: 'Timed message', prompt: 'Continue', recurrence: 'daily',
+      nextRunAt: '2026-09-10T00:00:00Z'
+    })
+    const item = database.queueScheduleNow(schedule.id)
+    expect(database.claimConversationQueueItem(schedule.conversationId)?.source).toBe('schedule')
+    expect(database.isConversationUserQueueItemDispatching(item.id)).toBe(true)
+    database.releaseConversationUserQueueItem(item.id)
+    expect(database.claimConversationQueueItem(schedule.conversationId)?.source).toBe('schedule')
+    database.createTask({ id: item.scheduleRunId!, conversationId: schedule.conversationId,
+      title: 'Continue', instructions: 'Continue', workMode: 'execute', visible: false })
+    database.completeConversationUserQueueItem(item.id)
+    database.updateTaskStatus(item.scheduleRunId!, 'completed')
+    database.completeTaskScheduleRun(item.scheduleRunId!)
+    database.completeTaskScheduleRun(item.scheduleRunId!)
+    database.close()
+    database.initialize('C:\\Workspace')
+    expect(database.listConversationQueueItems(schedule.conversationId)).toEqual([])
+    expect(database.listSchedules().find(candidate => candidate.id === schedule.id)?.lastRunAt).toBeDefined()
+    database.close()
+  })
+
+  it('does not resend an accepted scheduled message interrupted by a local restart', async () => {
+    const database = await createDatabase()
+    const schedule = database.createSchedule({
+      title: 'Timed message', prompt: 'Continue', recurrence: 'once',
+      nextRunAt: '2026-09-10T00:00:00Z'
+    })
+    const item = database.queueScheduleNow(schedule.id)
+    database.claimConversationQueueItem(schedule.conversationId)
+    database.createTask({ id: item.scheduleRunId!, conversationId: schedule.conversationId,
+      title: 'Continue', instructions: 'Continue', workMode: 'execute', visible: false })
+    database.completeConversationUserQueueItem(item.id)
+    database.close()
+    database.initialize('C:\\Workspace')
+    expect(database.listConversationQueueItems(schedule.conversationId)).toEqual([])
+    expect(database.listTasks().find(task => task.id === schedule.taskId)?.status).toBe('failed')
+    database.close()
+  })
   it('rejects a newer unsupported schema without changing its version', async () => {
     const directory = await mkdtemp(
       join(tmpdir(), 'goodbuddy-assistant-future-')
@@ -5221,7 +5295,7 @@ describe('AssistantDatabase', () => {
         },
         continueModelSource: { kind: 'platform' }
       })
-    ).toBe(4)
+    ).toBe(3)
     expect(
       database
         .listConversations()
@@ -5235,7 +5309,8 @@ describe('AssistantDatabase', () => {
       { provider: 'model', profileId: runtimeProfileId }
     ])
     expect(database.getProject(channelProject.id).runtimeSelection).toEqual({
-      provider: 'opencode'
+      provider: 'opencode',
+      profileId: runtimeProfileId
     })
     expect(
       database.getProject(imageChannelProject.id).runtimeSelection