fix: prevent Ctrl+V crash when clipboard contains non-text data

Two-layer fix for TypeError crash on paste:

1. _SafePyperclipClipboard: wraps PyperclipClipboard.get_data() to treat
   None/non-string payloads as empty text, protecting all clipboard access
   paths in prompt_toolkit (not just our Ctrl+V handler). Covers MoonshotAI#1750.

2. _try_paste_media() return value: when images are detected but the model
   does not support image_in, the paste event is now consumed (return True)
   instead of falling through to the text paste path.

Author: exqqstar

src/kimi_cli/ui/shell/prompt.py

@@ -21,6 +21,7 @@
 from prompt_toolkit import PromptSession
 from prompt_toolkit.application.current import get_app_or_none
 from prompt_toolkit.buffer import Buffer
+from prompt_toolkit.clipboard.base import ClipboardData
 from prompt_toolkit.clipboard.pyperclip import PyperclipClipboard
 from prompt_toolkit.completion import (
     CompleteEvent,
@@ -81,6 +82,24 @@
 PROMPT_SYMBOL_PLAN = "📋"
 
 
+class _SafePyperclipClipboard(PyperclipClipboard):
+    """Treat non-text clipboard payloads as empty text instead of crashing prompt_toolkit."""
+
+    @override
+    def get_data(self) -> ClipboardData:
+        try:
+            data = super().get_data()
+        except TypeError as exc:
+            logger.debug(
+                "Ignoring non-text clipboard payload in text paste handler: {error}",
+                error=exc,
+            )
+            return ClipboardData()
+        if not isinstance(data.text, str):
+            return ClipboardData()
+        return data
+
+
 class SlashCommandCompleter(Completer):
     """
     A completer that:
@@ -1488,7 +1507,7 @@ def _(event: KeyPressEvent) -> None:
                 self._insert_pasted_text(event.current_buffer, clipboard_data.text)
                 event.app.invalidate()
 
-            clipboard = PyperclipClipboard()
+            clipboard = _SafePyperclipClipboard()
         else:
             clipboard = None
 
@@ -1846,6 +1865,7 @@ def _try_paste_media(self, event: KeyPressEvent) -> bool:
             return False
 
         parts: list[str] = []
+        unsupported_images = False
 
         # 1. Insert file paths (videos, PDFs, etc.)
         if result.file_paths:
@@ -1859,6 +1879,7 @@ def _try_paste_media(self, event: KeyPressEvent) -> bool:
         # 2. Insert images via cache.
         if result.images:
             if "image_in" not in self._model_capabilities:
+                unsupported_images = True
                 console.print(
                     "[yellow]Image input is not supported by the selected LLM model[/yellow]"
                 )
@@ -1877,7 +1898,7 @@ def _try_paste_media(self, event: KeyPressEvent) -> bool:
         if parts:
             event.current_buffer.insert_text(" ".join(parts))
         event.app.invalidate()
-        return bool(parts)
+        return bool(parts) or unsupported_images
 
     def set_prefill_text(self, text: str) -> None:
         """Pre-fill the input buffer with the given text.

tests/ui_and_conv/test_prompt_clipboard.py

@@ -7,6 +7,7 @@
 
 from PIL import Image
 from prompt_toolkit.key_binding import KeyPressEvent
+from prompt_toolkit.selection import SelectionType
 
 if TYPE_CHECKING:
     from prompt_toolkit.buffer import Buffer
@@ -184,7 +185,7 @@ def test_paste_single_image(monkeypatch) -> None:
     assert buffer.inserted[0].startswith("[image:")
 
 
-def test_paste_image_unsupported_model(monkeypatch, capsys) -> None:
+def test_paste_image_unsupported_model_consumes_paste(monkeypatch, capsys) -> None:
     img = Image.new("RGB", (10, 10))
     monkeypatch.setattr(
         shell_prompt,
@@ -199,9 +200,11 @@ def test_paste_image_unsupported_model(monkeypatch, capsys) -> None:
 
     result = ps._try_paste_media(cast(KeyPressEvent, event))
 
-    # No image placeholder inserted, returns False so caller can fall back to text paste
-    assert result is False
+    # Media was recognized, so the paste event should be consumed even though the
+    # model cannot accept image input.
+    assert result is True
     assert buffer.inserted == []
+    assert app.invalidated is True
 
 
 # --- Mixed content tests ---
@@ -270,6 +273,19 @@ def test_paste_returns_false_when_no_media(monkeypatch) -> None:
     assert buffer.inserted == []
 
 
+def test_safe_pyperclip_clipboard_treats_none_as_empty_text(monkeypatch) -> None:
+    monkeypatch.setattr(
+        "prompt_toolkit.clipboard.pyperclip.pyperclip.paste",
+        lambda: None,
+    )
+
+    clipboard = shell_prompt._SafePyperclipClipboard()
+    data = clipboard.get_data()
+
+    assert data.text == ""
+    assert data.type == SelectionType.CHARACTERS
+
+
 def test_insert_pasted_text_placeholderizes_long_text_in_agent_mode() -> None:
     ps = _make_prompt_session(PromptMode.AGENT)
     buffer = _DummyBuffer()