fix(tui): remove alt+enter from newLine default keybinding

alt+enter is used by coding-agent for follow-up messages.
Having it also mapped to newLine caused a conflict.

packages/coding-agent/README.md

@@ -329,7 +329,7 @@ All keyboard shortcuts can be customized via `~/.pi/agent/keybindings.json`. Eac
 | `deleteWordBackward` | `ctrl+w`, `alt+backspace` | Delete word backward |
 | `deleteToLineStart` | `ctrl+u` | Delete to line start |
 | `deleteToLineEnd` | `ctrl+k` | Delete to line end |
-| `newLine` | `shift+enter`, `alt+enter` | Insert new line |
+| `newLine` | `shift+enter` | Insert new line |
 | `submit` | `enter` | Submit input |
 | `tab` | `tab` | Tab/autocomplete |
 | `interrupt` | `escape` | Interrupt operation |

packages/tui/src/keybindings.ts

@@ -61,7 +61,7 @@ export const DEFAULT_EDITOR_KEYBINDINGS: Required<EditorKeybindingsConfig> = {
 	deleteToLineStart: "ctrl+u",
 	deleteToLineEnd: "ctrl+k",
 	// Text input
-	newLine: ["shift+enter", "alt+enter"],
+	newLine: "shift+enter",
 	submit: "enter",
 	tab: "tab",
 	// Selection/autocomplete