refactor: standardize new game progress ui

- introduce shared progress indicator component for wizard steps
- align layouts and button sizing across new game panels
- update feature exports to surface the new component

Refs #30

src/lib/features/new-game/steps/Player2Step.tsx

@@ -1,6 +1,7 @@
 import { h } from 'preact';
 import { useEffect, useRef, useState } from 'preact/hooks';
 import styles from '../NewGame.module.css';
+import { ProgressIndicator } from '../ProgressIndicator';
 
 interface PlayerStepProps {
   playerNameHistory: string[];
@@ -52,15 +53,7 @@ export const Player2Step = ({ playerNameHistory, onNext, onCancel, initialValue
     <form className={styles['new-game-form']} onSubmit={handleSubmit} aria-label="Spieler 2 Eingabe" autoComplete="off">
       <div className={styles['form-header']}>
         <div className={styles['screen-title']}>Name Spieler 2</div>
-        <div className={styles['progress-indicator']} style={{ marginBottom: 24 }}>
-          <span className={styles['progress-dot']} />
-          <span className={styles['progress-dot'] + ' ' + styles['active']} />
-          <span className={styles['progress-dot']} />
-          <span className={styles['progress-dot']} />
-          <span className={styles['progress-dot']} />
-          <span className={styles['progress-dot']} />
-          <span className={styles['progress-dot']} />
-        </div>
+        <ProgressIndicator currentStep={2} style={{ marginBottom: 24 }} />
       </div>
       
       <div className={styles['form-content']}>