fix(runtime): bound terminal-wait blocked-prompt rules to the live screen bottom (#18817)

The Codex prompt rules in terminal-wait-detection scanned the whole retained
tail (up to 256 KiB) with lastIndexOf, so any quoted prompt phrase in
scrollback registered as a live prompt. A Codex agent working on Orca prints
rg hits from this very file; one such line ~300 lines above an idle input box
made `orca terminal send` refuse with agent_prompt_blocked and `terminal wait
--for tui-idle` report codex-interactive-prompt. `clear` did not help because
the detector reads the retained tail, not the visible screen.

A prompt that owns the terminal is at the screen bottom, so every blocked
rule now runs over the last 12 non-blank lines (real Codex dialogs are 4-8
lines), the way the cursor approval rule already was. The returned index is
offset back into full-tail coordinates so ready-header comparisons keep
working. The sentinel fast path is unchanged.

Line-window primitives move to terminal-wait-tail-window.ts to keep the
detector under the max-lines cap.

src/main/runtime/terminal-wait-detection.test.ts

@@ -0,0 +1,200 @@
+import { describe, expect, it } from 'vitest'
+import {
+  detectTerminalWaitBlockedReason,
+  isKnownReadyPromptPreview
+} from './terminal-wait-detection'
+import { buildTerminalWaitText } from './terminal-wait-tail-state'
+
+// Why these shapes: Codex agents working on Orca print `rg` hits from this very detector and its
+// specs, so quoted prompt wording lands in scrollback while the terminal sits at its input box.
+const QUOTED_DETECTOR_SOURCE_LINE =
+  "└   if (hooksindex !== -1 && normalized.includes('press enter to confirm', hooksindex)) {"
+const QUOTED_PERMISSION_FIXTURE_LINE =
+  "  └ 236:      'Permission required\\nThis command requires permission\\nAllow once\\nAllow always\\nReject\\n',"
+
+function codexIdleScreen(): string[] {
+  return [
+    '• Done. The detector bounding is in place and the suite passes.',
+    '',
+    '› Ask Codex to do anything',
+    '',
+    '  gpt-6-astra medium · ~/orca/workspaces/orca/fix-wait-detector-scrollback'
+  ]
+}
+
+function codexScrollback(quotedLines: string[], trailingLineCount: number): string[] {
+  const lines: string[] = [
+    '• Explored',
+    '  └ Search press enter to confirm in src/main/runtime',
+    '    Read terminal-wait-detection.ts',
+    '',
+    '• Ran rg -n "press enter to confirm" src/main/runtime/terminal-wait-detection.ts src/main/runtime/orca-runtime-tests/agent-status-and-waits.spec.ts',
+    '  └ src/main/runtime/terminal-wait-detection.ts',
+    '    src/main/runtime/orca-runtime-tests/agent-status-and-waits.spec.ts',
+    '    src/main/runtime/orca-runtime-tests/terminal-creation-and-readiness-part-07.spec.ts',
+    ...quotedLines
+  ]
+  for (let index = 0; index < trailingLineCount; index += 1) {
+    lines.push(`    ${index}: unrelated codex narration about hook wiring and sandbox policy`)
+  }
+  return lines
+}
+
+function waitTextFor(lines: string[]): string {
+  return buildTerminalWaitText(lines, '', '')
+}
+
+describe('detectTerminalWaitBlockedReason scrollback bounding', () => {
+  it('ignores detector source quoted by rg output far above an idle Codex input box', () => {
+    const waitText = waitTextFor([
+      ...codexScrollback([QUOTED_DETECTOR_SOURCE_LINE], 300),
+      ...codexIdleScreen()
+    ])
+
+    expect(waitText).toContain('press enter to confirm')
+    expect(detectTerminalWaitBlockedReason(waitText)).toBeNull()
+  })
+
+  it('ignores a quoted permission fixture in scrollback above an idle Codex input box', () => {
+    const waitText = waitTextFor([
+      ...codexScrollback([QUOTED_PERMISSION_FIXTURE_LINE], 300),
+      ...codexIdleScreen()
+    ])
+
+    expect(waitText.toLowerCase()).toContain('allow once')
+    expect(detectTerminalWaitBlockedReason(waitText)).toBeNull()
+  })
+
+  it('ignores quoted prompt wording just above the live-dialog window', () => {
+    // Why 10: with the 3-line idle screen the quoted lines sit 13-14 non-blank lines from the bottom.
+    const waitText = waitTextFor([
+      ...codexScrollback([QUOTED_DETECTOR_SOURCE_LINE, QUOTED_PERMISSION_FIXTURE_LINE], 10),
+      ...codexIdleScreen()
+    ])
+
+    expect(detectTerminalWaitBlockedReason(waitText)).toBeNull()
+  })
+
+  it('does not let quoted scrollback wording veto a Codex ready header', () => {
+    const waitText = waitTextFor([
+      ...codexScrollback([QUOTED_PERMISSION_FIXTURE_LINE], 40),
+      ' >_ OpenAI Codex (v0.153.3)',
+      ' model:       gpt-6-astra medium   /model to change',
+      ' directory:   ~/orca/workspaces/orca/fix-wait-detector-scrollback'
+    ])
+
+    expect(isKnownReadyPromptPreview(waitText)).toBe(true)
+  })
+})
+
+// Real dialog text: terminal-creation-and-readiness-part-07.spec.ts and agent-status-and-waits.spec.ts.
+const LIVE_CODEX_PROMPTS: { name: string; lines: string[]; reason: string }[] = [
+  {
+    name: 'hooks review',
+    lines: [
+      'Hooks need review',
+      '2 hooks are new or changed.',
+      '1. Review hooks',
+      '2. Trust all and continue',
+      'Press enter to confirm or esc to go back'
+    ],
+    reason: 'codex-hooks-review-prompt'
+  },
+  {
+    name: 'trust workspace',
+    lines: ['Do you trust this workspace directory?', '1. Yes', '2. No'],
+    reason: 'codex-trust-workspace'
+  },
+  {
+    name: 'update',
+    lines: [
+      'Update available! 0.131.0 -> 0.132.0',
+      '1. Update now',
+      '2. Skip',
+      'Press enter to continue'
+    ],
+    reason: 'codex-update-prompt'
+  },
+  {
+    name: 'cwd selection',
+    lines: [
+      'Choose working directory to resume this session',
+      '  Session = latest cwd recorded in the resumed session',
+      '  Current = your current working directory',
+      '  Press enter to continue'
+    ],
+    reason: 'codex-cwd-prompt'
+  },
+  {
+    name: 'model migration',
+    lines: [
+      'Codex just got an upgrade. Introducing gpt-5.1-codex-max.',
+      'We recommend switching from gpt-5-codex to gpt-5.1-codex-max.',
+      'Press enter to continue'
+    ],
+    reason: 'codex-model-migration-prompt'
+  },
+  {
+    name: 'grant permissions',
+    lines: [
+      'Would you like to grant these permissions?',
+      '1. Yes, grant these permissions for this turn',
+      '2. No, continue without permissions',
+      'Press enter to confirm or esc to cancel'
+    ],
+    reason: 'codex-interactive-prompt'
+  },
+  {
+    name: 'permission required',
+    lines: [
+      'Permission required',
+      'This command requires permission',
+      'Allow once',
+      'Allow always',
+      'Reject'
+    ],
+    reason: 'codex-interactive-prompt'
+  }
+]
+
+describe('detectTerminalWaitBlockedReason live prompts', () => {
+  for (const prompt of LIVE_CODEX_PROMPTS) {
+    it(`still blocks on a live ${prompt.name} prompt after long scrollback`, () => {
+      const waitText = waitTextFor([
+        ...codexScrollback([QUOTED_DETECTOR_SOURCE_LINE, QUOTED_PERMISSION_FIXTURE_LINE], 300),
+        ...prompt.lines
+      ])
+
+      expect(detectTerminalWaitBlockedReason(waitText)).toBe(prompt.reason)
+    })
+
+    it(`blocks on a live ${prompt.name} prompt rendered with blank spacer rows`, () => {
+      // Why: the visible-screen probe joins raw rows, so blank rows between dialog lines must not eat the window.
+      const spaced = prompt.lines.flatMap((line) => [line, '', ''])
+      const screen = [
+        ' >_ OpenAI Codex (v0.153.3)',
+        '',
+        ...spaced,
+        '',
+        '  gpt-6-astra medium · ~/orca/workspaces/orca/fix-wait-detector-scrollback',
+        ''
+      ].join('\n')
+
+      expect(detectTerminalWaitBlockedReason(screen)).toBe(prompt.reason)
+    })
+  }
+
+  it('reports the newest prompt when a live dialog follows a stale one at the bottom', () => {
+    const waitText = waitTextFor([
+      'Update available! 0.131.0 -> 0.132.0',
+      'Press enter to continue',
+      ' >_ OpenAI Codex (v0.132.0)',
+      ' model:       gpt-5.5 high   /model to change',
+      ' directory:   ~/orca/workspaces/orca/cli-debug',
+      'Hooks need review',
+      'Press enter to confirm'
+    ])
+
+    expect(detectTerminalWaitBlockedReason(waitText)).toBe('codex-hooks-review-prompt')
+  })
+})

src/main/runtime/terminal-wait-detection.ts

@@ -4,6 +4,11 @@ import {
   type AgentStatus
 } from '../../shared/agent-detection'
 import type { RuntimeTerminalWaitBlockedReason } from '../../shared/runtime-types'
+import {
+  isTerminalWaitWhitespace,
+  startOfLastLines,
+  startOfLastNonBlankLines
+} from './terminal-wait-tail-window'
 
 const EXPLICIT_IDLE_TITLE_RE = /(^|\s)(ready|idle|done)(\s|$|[.!?])/i
 const CLAUDE_IDLE_PREFIX = '\u2733'
@@ -153,11 +158,6 @@ function findAntigravityReadyPromptIndex(normalized: string): number | null {
   return modelIndex !== null && promptIndex !== null ? Math.max(modelIndex, promptIndex) : null
 }
 
-function isTerminalWaitWhitespace(value: string, index: number): boolean {
-  const code = value.charCodeAt(index)
-  return code === 32 || (code >= 9 && code <= 13)
-}
-
 export const TERMINAL_WAIT_BLOCKED_SENTINEL_RE =
   /update available|choose working directory to|codex just got an upgrade|hooks need review|do you trust|trust this|trusted workspace|press enter to (?:confirm|continue|view|insert)|press t to trust|permission required|requires permission|allow once|allow always|run this command\?/i
 
@@ -206,25 +206,28 @@ function isCursorApprovalChoiceLine(line: string): boolean {
   )
 }
 
-function startOfLastLines(value: string, count: number): number {
-  let cursor = value.length
-  for (let seen = 0; seen < count; seen += 1) {
-    const previous = value.lastIndexOf('\n', cursor - 1)
-    if (previous === -1) {
-      return 0
-    }
-    cursor = previous
-  }
-  return cursor + 1
-}
+// Why bounded: answered dialogs and quoted prompt wording (agents grep this file and its specs) stay in the
+// retained tail; only a dialog owning the screen bottom is live. Real Codex dialogs (trust, hooks review,
+// update, exec approval) are 4-8 lines; the slack covers a wrapped command or a longer hook list.
+const LIVE_PROMPT_TAIL_LINES = 12
 
 function findTerminalWaitBlockedSignal(
-  normalized: string
+  fullTail: string
 ): { reason: RuntimeTerminalWaitBlockedReason; index: number } | null {
-  // Why: one combined negative scan over the up-to-256 KiB tail avoids a dozen full-tail searches when no prompt can match.
+  const windowStart = startOfLastNonBlankLines(fullTail, LIVE_PROMPT_TAIL_LINES)
+  const normalized = windowStart === 0 ? fullTail : fullTail.slice(windowStart)
+  // Why: one combined negative scan avoids a dozen searches when no prompt can match.
   if (!TERMINAL_WAIT_BLOCKED_SENTINEL_RE.test(normalized)) {
     return null
   }
+  const signal = findBlockedSignalInLiveWindow(normalized)
+  // Why: callers compare this index against ready-header indexes found over the full tail.
+  return signal === null ? null : { reason: signal.reason, index: signal.index + windowStart }
+}
+
+function findBlockedSignalInLiveWindow(
+  normalized: string
+): { reason: RuntimeTerminalWaitBlockedReason; index: number } | null {
   const candidates: { reason: RuntimeTerminalWaitBlockedReason; index: number }[] = []
   const updateIndex = normalized.lastIndexOf('update available')
   if (updateIndex !== -1 && normalized.includes('press enter to continue', updateIndex)) {

src/main/runtime/terminal-wait-tail-window.ts

@@ -0,0 +1,48 @@
+// Line-window primitives over a newline-joined terminal tail, shared by the wait-blocked prompt rules.
+
+export function isTerminalWaitWhitespace(value: string, index: number): boolean {
+  const code = value.charCodeAt(index)
+  return code === 32 || (code >= 9 && code <= 13)
+}
+
+/** Offset where the last `count` lines begin (0 when the tail is shorter). */
+export function startOfLastLines(value: string, count: number): number {
+  let cursor = value.length
+  for (let seen = 0; seen < count; seen += 1) {
+    const previous = value.lastIndexOf('\n', cursor - 1)
+    if (previous === -1) {
+      return 0
+    }
+    cursor = previous
+  }
+  return cursor + 1
+}
+
+/** Like `startOfLastLines`, but blank rows don't count toward the window. */
+// Why: the visible-screen probe joins raw rows, so blank spacer rows must not eat a dialog's window.
+export function startOfLastNonBlankLines(value: string, count: number): number {
+  let seen = 0
+  let lineEnd = value.length
+  for (;;) {
+    const lineStart = value.lastIndexOf('\n', lineEnd - 1) + 1
+    if (hasNonWhitespaceBetween(value, lineStart, lineEnd)) {
+      seen += 1
+      if (seen >= count) {
+        return lineStart
+      }
+    }
+    if (lineStart === 0) {
+      return 0
+    }
+    lineEnd = lineStart - 1
+  }
+}
+
+function hasNonWhitespaceBetween(value: string, start: number, end: number): boolean {
+  for (let index = start; index < end; index += 1) {
+    if (!isTerminalWaitWhitespace(value, index)) {
+      return true
+    }
+  }
+  return false
+}