Support native-prefill prompt delivery and fix chat message sorting

* Treat native draft pre-fills as successful deliveries instead of
  marking the seeded launch prompts as failed.
* Group native chat messages into sorting tiers (real content, streaming
  preview, optimistic echoes) so optimistic bubbles don't sort past
  the streaming preview due to finite timestamps.

src/renderer/src/components/native-chat/native-chat-message-grouping.test.ts

@@ -33,13 +33,13 @@ describe('orderNativeChatMessages', () => {
     expect(ordered.map((m) => m.id)).toEqual(['a', 'z'])
   })
 
-  it('sorts the synthetic streaming message after timestamped content', () => {
+  it('sorts the streaming preview after real content but before optimistic echoes', () => {
     const ordered = orderNativeChatMessages([
+      msg({ id: 'pending:abc', role: 'user', timestamp: 20, source: 'scrape' }),
       msg({ id: NATIVE_CHAT_STREAMING_ID, timestamp: null }),
-      msg({ id: 'real-user', role: 'user', timestamp: 10 }),
-      msg({ id: 'pending-user', role: 'user', timestamp: 20, source: 'scrape' })
+      msg({ id: 'real-user', role: 'user', timestamp: 10 })
     ])
-    expect(ordered.map((m) => m.id)).toEqual(['real-user', 'pending-user', 'streaming'])
+    expect(ordered.map((m) => m.id)).toEqual(['real-user', 'streaming', 'pending:abc'])
   })
 })
 

src/renderer/src/components/native-chat/native-chat-pending.ts

@@ -153,6 +153,9 @@ export function isPendingMessageId(id: string): boolean {
   return id.startsWith('pending:')
 }
 
+// Why: the seeded prompt has a synthetic id that never matches the real turn's,
+// so dedup/prune match on normalized user-message text instead — this hides the
+// optimistic bubble once the transcript's own copy of the turn catches up.
 export function launchPromptAsMessage(
   entry: NativeChatLaunchPrompt | null,
   existingMessages: NativeChatMessage[] = []

src/renderer/src/components/native-chat/native-chat-session-assembler.ts

@@ -8,6 +8,7 @@ import {
 } from '../../../../shared/native-chat-types'
 import { NATIVE_CHAT_STREAMING_ID } from '../../../../shared/native-chat-streaming'
 import { normalizeImageTranscriptMessages } from './native-chat-image-transcript-markers'
+import { isLaunchPromptMessageId, isPendingMessageId } from './native-chat-pending'
 
 /** Messages grouped by source. Higher-priority sources (transcript > hook >
  *  scrape) supersede lower ones when they describe the same turn. */
@@ -85,20 +86,31 @@ function supersedes(candidate: NativeChatMessage, existing: NativeChatMessage):
   return candidateRank > existingRank
 }
 
-function messageSortTimestamp(message: NativeChatMessage): number {
+// Why: the tail bubbles form fixed tiers that timestamps alone can't express.
+// The streaming preview (null timestamp) must follow real content but sit ahead
+// of the optimistic composer echoes, which carry finite `sentAt` timestamps that
+// would otherwise sort past it. Rank first, then timestamp within a tier.
+function messageSortRank(message: NativeChatMessage): number {
   if (message.id === NATIVE_CHAT_STREAMING_ID) {
-    return Number.POSITIVE_INFINITY
+    return 1
   }
-  return message.timestamp ?? Number.NEGATIVE_INFINITY
+  if (isPendingMessageId(message.id) || isLaunchPromptMessageId(message.id)) {
+    return 2
+  }
+  return 0
 }
 
 // Why: null timestamps (sources that can't supply one, e.g. scrape segments)
-// sort before any real timestamp so they don't jump to the end. The synthetic
-// streaming preview is the one exception: it is a tail bubble and sorts last.
-// Ties break on id for a stable, deterministic order.
+// sort before any real timestamp within their tier so they don't jump to the
+// end. Ties break on id for a stable, deterministic order.
 export function compareMessages(a: NativeChatMessage, b: NativeChatMessage): number {
-  const at = messageSortTimestamp(a)
-  const bt = messageSortTimestamp(b)
+  const ar = messageSortRank(a)
+  const br = messageSortRank(b)
+  if (ar !== br) {
+    return ar - br
+  }
+  const at = a.timestamp ?? Number.NEGATIVE_INFINITY
+  const bt = b.timestamp ?? Number.NEGATIVE_INFINITY
   if (at !== bt) {
     return at - bt
   }

src/renderer/src/lib/agent-launch-prompt-delivery.test.ts

@@ -97,6 +97,25 @@ describe('deliverLaunchPromptToAgentTab', () => {
     expect(mocks.markNativeChatLaunchPromptFailed).toHaveBeenCalledWith('tab-1')
   })
 
+  it('treats native-prefill delivery as success without flagging the seeded prompt', async () => {
+    // claude delivers via `--prefill` at launch, so paste no-ops (returns false)
+    // when forcePaste is false — that is a native delivery, not a failure.
+    mocks.pasteDraftWhenAgentReady.mockResolvedValue(false)
+
+    await expect(
+      deliverLaunchPromptToAgentTab({
+        tabId: 'tab-1',
+        agent: 'claude',
+        content: 'Large generated prompt',
+        submit: true,
+        forcePaste: false
+      })
+    ).resolves.toBe(true)
+
+    expect(mocks.seedNativeChatLaunchPrompt).toHaveBeenCalled()
+    expect(mocks.markNativeChatLaunchPromptFailed).not.toHaveBeenCalled()
+  })
+
   it('does not mark unseeded launches failed', async () => {
     mocks.pasteDraftWhenAgentReady.mockResolvedValue(false)
 

src/renderer/src/lib/agent-launch-prompt-delivery.ts

@@ -1,3 +1,4 @@
+import { agentDeliversDraftViaNativePrefill } from '@/lib/agent-native-draft-prefill'
 import { pasteDraftWhenAgentReady } from '@/lib/agent-paste-draft'
 import { isNativeChatSupportedAgent } from '@/lib/native-chat-supported-agent'
 import { useAppStore } from '@/store'
@@ -25,6 +26,11 @@ export function deliverLaunchPromptToAgentTab(args: {
     })
   }
 
+  // Why: native-prefill agents (claude/openclaude etc.) get the prompt at launch,
+  // so pasteDraftWhenAgentReady returns false without pasting. That is a successful
+  // native delivery, not a failure — don't flag the seeded bubble in that case.
+  const deliversViaNativePrefill = agentDeliversDraftViaNativePrefill(agent, forcePaste)
+
   return pasteDraftWhenAgentReady({
     tabId,
     content,
@@ -34,9 +40,9 @@ export function deliverLaunchPromptToAgentTab(args: {
     timeoutMs,
     onTimeout
   }).then((delivered) => {
-    if (shouldSeed && !delivered) {
+    if (shouldSeed && !delivered && !deliversViaNativePrefill) {
       useAppStore.getState().markNativeChatLaunchPromptFailed(tabId)
     }
-    return delivered
+    return delivered || deliversViaNativePrefill
   })
 }

src/renderer/src/lib/agent-native-draft-prefill.ts

@@ -0,0 +1,17 @@
+import type { TuiAgent } from '../../../shared/types'
+import { TUI_AGENT_CONFIG } from '../../../shared/tui-agent-config'
+
+// Why: agents with a native draft-prefill flag/env launch with the prompt
+// already in their input box, so the paste helpers intentionally no-op (return
+// false) unless `forcePaste` overrides. Callers use this to tell "delivered
+// natively" apart from a real paste failure.
+export function agentDeliversDraftViaNativePrefill(
+  agent: TuiAgent | undefined,
+  forcePaste: boolean | undefined
+): boolean {
+  if (forcePaste) {
+    return false
+  }
+  const agentConfig = agent ? TUI_AGENT_CONFIG[agent] : null
+  return Boolean(agentConfig?.draftPromptFlag || agentConfig?.draftPromptEnvVar)
+}

src/renderer/src/lib/agent-paste-draft.ts

@@ -14,6 +14,7 @@ import { waitForAgentReady } from './agent-ready-wait'
 import { getSettingsForWorktreeRuntimeOwner } from './worktree-runtime-owner'
 import type { GlobalSettings } from '../../../shared/types'
 import { sendAgentDraftPasteContent } from './agent-draft-paste-content'
+import { agentDeliversDraftViaNativePrefill } from './agent-native-draft-prefill'
 import { waitForAgentDraftInputReady } from './agent-draft-readiness'
 import { isExpectedAgentProcess } from '../../../shared/agent-process-recognition'
 export {
@@ -91,7 +92,7 @@ export async function pasteDraftWhenAgentReady(args: {
   // duplicate it. Callers should not invoke this helper for those agents;
   // the early return guards against accidental double-injection if a stale
   // call slips through.
-  if (!forcePaste && (agentConfig?.draftPromptFlag || agentConfig?.draftPromptEnvVar)) {
+  if (agentDeliversDraftViaNativePrefill(agent, forcePaste)) {
     return false
   }
 
@@ -140,7 +141,7 @@ export async function pasteDraftToAgentPtyWhenReady(args: {
   const { tabId, ptyId, content, agent, submit, forcePaste, timeoutMs, onTimeout } = args
   const agentConfig = agent ? TUI_AGENT_CONFIG[agent] : null
 
-  if (!forcePaste && (agentConfig?.draftPromptFlag || agentConfig?.draftPromptEnvVar)) {
+  if (agentDeliversDraftViaNativePrefill(agent, forcePaste)) {
     return false
   }