fix(tui): recover from stuck paste mode

Prevent unterminated bracketed paste input from swallowing future keystrokes, and avoid rendering an empty Thinking panel before reasoning arrives.

ui-tui/packages/hermes-ink/src/ink/parse-keypress.test.ts

@@ -0,0 +1,41 @@
+import { describe, expect, it } from 'vitest'
+
+import { INITIAL_STATE, parseMultipleKeypresses } from './parse-keypress.js'
+import { PASTE_END, PASTE_START } from './termio/csi.js'
+
+describe('parseMultipleKeypresses bracketed paste recovery', () => {
+  it('emits empty bracketed pastes when the terminal sends both markers', () => {
+    const [keys, state] = parseMultipleKeypresses(INITIAL_STATE, PASTE_START + PASTE_END)
+
+    expect(keys).toHaveLength(1)
+    expect(keys[0]).toMatchObject({ isPasted: true, raw: '' })
+    expect(state.mode).toBe('NORMAL')
+  })
+
+  it('flushes unterminated paste content back to normal input mode', () => {
+    const [pendingKeys, pendingState] = parseMultipleKeypresses(INITIAL_STATE, PASTE_START + 'hello')
+
+    expect(pendingKeys).toEqual([])
+    expect(pendingState.mode).toBe('IN_PASTE')
+
+    const [keys, state] = parseMultipleKeypresses(pendingState, null)
+
+    expect(keys).toHaveLength(1)
+    expect(keys[0]).toMatchObject({ isPasted: true, raw: 'hello' })
+    expect(state.mode).toBe('NORMAL')
+    expect(state.pasteBuffer).toBe('')
+  })
+
+  it('resets an empty unterminated paste start instead of staying stuck', () => {
+    const [pendingKeys, pendingState] = parseMultipleKeypresses(INITIAL_STATE, PASTE_START)
+
+    expect(pendingKeys).toEqual([])
+    expect(pendingState.mode).toBe('IN_PASTE')
+
+    const [keys, state] = parseMultipleKeypresses(pendingState, null)
+
+    expect(keys).toEqual([])
+    expect(state.mode).toBe('NORMAL')
+    expect(state.pasteBuffer).toBe('')
+  })
+})