fix(prompt): drop the unsupported default option from the text prompt

src/utils/prompt.ts

@@ -33,17 +33,32 @@ export async function promptText(options: {
   const { defaultValue, message } = options;
   const inquirer = await import('@clack/prompts');
   // eslint-disable-next-line @typescript-eslint/no-explicit-any
-  const val = await (inquirer as any).text({
-    message,
-    default: defaultValue,
-    placeholder: defaultValue,
-  });
+  const val = await (inquirer as any).text(textPromptOptions(message, defaultValue));
 
   // @clack/prompts returns a Symbol.cancel when the user presses Ctrl+C
   if (typeof val === 'symbol') return undefined;
   return val as string;
 }
 
+/**
+ * Build the options for a text prompt.
+ *
+ * A default value is presented as a placeholder rather than as the prompt's
+ * actual value, so a hint can never be submitted as input text.
+ *
+ * @clack/prompts has no `default` option (its option is `defaultValue`), so
+ * passing one alongside `placeholder` never had any effect.
+ */
+export function textPromptOptions(message: string, defaultValue?: string): {
+  message: string;
+  placeholder?: string;
+} {
+  return {
+    message,
+    ...(defaultValue === undefined ? {} : { placeholder: defaultValue }),
+  };
+}
+
 const API_KEY_VISIBLE_LENGTH = 30;
 
 export function apiKeyPreview(value: string): string {

test/utils/prompt.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, it } from 'bun:test';
 
-import { apiKeyPreview } from '../../src/utils/prompt';
+import { apiKeyPreview, textPromptOptions } from '../../src/utils/prompt';
 
 describe('apiKeyPreview', () => {
   it('shows the total length only when the key is truncated', () => {
@@ -9,3 +9,18 @@ describe('apiKeyPreview', () => {
     expect(apiKeyPreview('a'.repeat(125))).toBe(`${'a'.repeat(30)}.... (125 chars)`);
   });
 });
+
+describe('textPromptOptions', () => {
+  it('keeps the placeholder separate from the editable value', () => {
+    expect(textPromptOptions('Enter a value:', 'Ask Mcode')).toEqual({
+      message: 'Enter a value:',
+      placeholder: 'Ask Mcode',
+    });
+  });
+
+  it('does not pass a default value as the prompt input', () => {
+    expect(textPromptOptions('Enter a value:')).toEqual({
+      message: 'Enter a value:',
+    });
+  });
+});