docs: Beta-Flyer-Formulierung für Skipper/Crew-Fotos präzisieren

Feature-Text nennt Avatarbilder statt Foto-Anhänge; PDF entsprechend aktualisiert.

Co-authored-by: Cursor <cursoragent@cursor.com>

docs/marketing/beta-flyer.html

@@ -322,7 +322,7 @@
       <div class="feature"><span class="feature-icon">✦</span><span>GPS-Track Upload (GPX/KML) mit Kartendarstellung</span></div>
       <div class="feature"><span class="feature-icon">✦</span><span>Streckenstatistik</span></div>
       <div class="feature"><span class="feature-icon">✦</span><span>Foto-Anhänge pro Reisetag</span></div>
-      <div class="feature"><span class="feature-icon">✦</span><span>Foto-Anhänge für Skipper und Crew</span></div>
+      <div class="feature"><span class="feature-icon">✦</span><span>Foto-Avatarbilder für Skipper und Crew</span></div>
       <div class="feature"><span class="feature-icon">✦</span><span>Crew einladen — gemeinsam am Logbuch arbeiten</span></div>
       <div class="feature"><span class="feature-icon">✦</span><span>PDF- &amp; CSV-Export</span></div>
       <div class="feature"><span class="feature-icon">✦</span><span>Verschlüsseltes Backup &amp; Wiederherstellung</span></div>