Add terminal setup command for Shift+Enter and Ctrl+Enter support (#3289)

Co-authored-by: jacob314 <jacob314@gmail.com>

packages/cli/src/config/keyBindings.ts

@@ -129,20 +129,24 @@ export const defaultKeyBindings: KeyBindingConfig = {
 
   // Text input
   // Original: key.name === 'return' && !key.ctrl && !key.meta && !key.paste
+  // Must also exclude shift to allow shift+enter for newline
   [Command.SUBMIT]: [
     {
       key: 'return',
       ctrl: false,
       command: false,
       paste: false,
+      shift: false,
     },
   ],
   // Original: key.name === 'return' && (key.ctrl || key.meta || key.paste)
   // Split into multiple data-driven bindings
+  // Now also includes shift+enter for multi-line input
   [Command.NEWLINE]: [
     { key: 'return', ctrl: true },
     { key: 'return', command: true },
     { key: 'return', paste: true },
+    { key: 'return', shift: true },
   ],
 
   // External tools