fix: resolve remaining TypeScript compilation errors

- Add placeholder property to TextFieldMD3 component and props interface
- Fix vite.config.ts to import defineConfig from vitest/config instead of vite
- Add type guard for validate property in schemas/index.ts to handle readonly array union types
- Remove unused StepIndicatorWithDispatch placeholder function from tests

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

src/components/ui/TextFieldMD3.tsx

@@ -6,6 +6,7 @@ interface TextFieldMD3Props {
   error?: FieldError;
   registration: UseFormRegisterReturn;
   type?: 'text' | 'password';
+  placeholder?: string;
   helpText?: string;
   helpTextPrefix?: React.ReactNode;
   required?: boolean;
@@ -18,6 +19,7 @@ export function TextFieldMD3({
   error,
   registration,
   type = 'text',
+  placeholder,
   helpText,
   helpTextPrefix,
   required,
@@ -29,7 +31,7 @@ export function TextFieldMD3({
         <input
           id={id}
           type={type}
-          placeholder=" "
+          placeholder={placeholder || " "}
           className={[
             'peer w-full rounded-md border bg-transparent px-3 pb-2 pt-5 text-sm text-on-surface',
             'placeholder-transparent focus:outline-none focus:ring-2',

src/components/wizard/StepIndicator.test.tsx

@@ -163,8 +163,3 @@ describe('StepIndicator', () => {
     });
   });
 });
-
-// Placeholder type for the spy component — not actually used in tests
-function StepIndicatorWithDispatch(_props: { dispatch: (action: { type: string; payload?: unknown }) => void }) {
-  return null;
-}

src/schemas/index.ts

@@ -15,7 +15,7 @@ function buildZodSchema(backendType: BackendType): z.ZodObject<Record<string, z.
       ? z.string().min(1, `${field.label} is required`)
       : z.string();
 
-    if (field.validate) {
+    if ('validate' in field && field.validate) {
       schema = (schema as z.ZodString).regex(field.validate.regex, field.validate.message);
     }
 

vite.config.ts

@@ -1,4 +1,4 @@
-import { defineConfig } from 'vite';
+import { defineConfig } from 'vitest/config';
 import react from '@vitejs/plugin-react';
 import tailwindcss from '@tailwindcss/vite';