Fix F3: use known-tag predicate for explicit-turn decisions

isHarnessInjectedUserTurnText matches any multi-word kebab tag, which is
safe for non-destructive UI classification but wrong for state-transition
decisions: a real prompt starting with a custom <my-element> paste looked
like machinery in resolvePrompt/hasExplicitUserPrompt. Combined with the
post-interrupt working-suppression in agent-hooks/server.ts, that left the
agent visibly done after Ctrl+C. Switch both explicit-turn callsites to the
known-tag isKnownHarnessInjectedUserTurnText predicate; known harness tags
and Grok <user_query> behave unchanged.

Co-authored-by: Orca <help@stably.ai>

src/shared/agent-hook-listener.test.ts

@@ -923,6 +923,49 @@ describe('shared agent-hook-listener', () => {
     expect(event!.hasExplicitPrompt).toBe(false)
   })
 
+  it('treats a custom-element paste as an explicit user turn, not machinery', () => {
+    normalizeHookPayload(
+      state,
+      'claude',
+      { paneKey: PANE_KEY, payload: { hook_event_name: 'UserPromptSubmit', prompt: 'fix login' } },
+      'production'
+    )
+    // Why: a real prompt starting with an unknown kebab tag (<my-custom-element>)
+    // is the user's turn — it must reset the cached prompt and count as explicit,
+    // so interrupt recovery does not leave the pane visibly done.
+    const event = normalizeHookPayload(
+      state,
+      'claude',
+      {
+        paneKey: PANE_KEY,
+        payload: {
+          hook_event_name: 'UserPromptSubmit',
+          prompt: '<my-custom-element> render this component'
+        }
+      },
+      'production'
+    )
+    expect(event).not.toBeNull()
+    expect(event!.payload.prompt).toBe('<my-custom-element> render this component')
+    expect(event!.hasExplicitPrompt).toBe(true)
+  })
+
+  it('treats a Grok user_query prompt as an explicit user turn', () => {
+    const event = normalizeHookPayload(
+      state,
+      'grok',
+      {
+        paneKey: PANE_KEY,
+        payload: { hookEventName: 'user_prompt_submit', prompt: '<user_query>fix the bug</user_query>' }
+      },
+      'production'
+    )
+    expect(event).not.toBeNull()
+    // Grok wraps the real typed prompt; the envelope is stripped but it stays explicit.
+    expect(event!.payload.prompt).toBe('fix the bug')
+    expect(event!.hasExplicitPrompt).toBe(true)
+  })
+
   it('isolates caches between listener instances', () => {
     const a = createHookListenerState()
     const b = createHookListenerState()

src/shared/agent-hook-listener.ts

@@ -52,7 +52,7 @@ import {
   type AgentProviderSessionMetadata
 } from './agent-session-resume'
 import { parsePaneKey } from './stable-pane-id'
-import { isHarnessInjectedUserTurnText } from './harness-injected-user-turns'
+import { isKnownHarnessInjectedUserTurnText } from './harness-injected-user-turns'
 import {
   buildGrokChatHistoryPathCandidates,
   findGrokChatHistoryBySessionId,
@@ -451,8 +451,10 @@ function resolvePrompt(
 ): string {
   // Why: harness-injected turns (task notifications, system reminders) fire
   // UserPromptSubmit but are not the user's ask — keep the cached real prompt
-  // instead of surfacing raw machinery tags in status labels.
-  if (isHarnessInjectedUserTurnText(promptText)) {
+  // instead of surfacing raw machinery tags in status labels. Match only known
+  // harness tags: a real prompt pasting a custom `<my-element>` must reset the
+  // turn, not be mistaken for machinery and leave the pane on a stale prompt.
+  if (isKnownHarnessInjectedUserTurnText(promptText)) {
     return state.lastPromptByPaneKey.get(paneKey) ?? ''
   }
   if (options?.resetOnNewTurn) {
@@ -2266,7 +2268,10 @@ function hasExplicitUserPrompt(
   }
   // Why: harness-injected machinery turns are not proof of a user submit —
   // they must not count for prompt-sent telemetry or permission stickiness.
-  if (isHarnessInjectedUserTurnText(extractedPrompt.text)) {
+  // Match only known harness tags: a real prompt starting with a custom
+  // `<my-element>` is an explicit user turn and must survive interrupt recovery
+  // (a false "not explicit" leaves the agent visibly done after Ctrl+C).
+  if (isKnownHarnessInjectedUserTurnText(extractedPrompt.text)) {
     return false
   }
   // Why: bare `message` fields often contain permission or status copy. They