Replace emoji icons with local SVG files for consistent rendering

- Created 10 SVG icon files in app/static/icons/ (Feather Icons style)
- Updated base.html with SVG icons in navigation and dark mode toggle
- Updated dashboard.html with icons in stats cards and quick actions
- Updated content_list_new.html (playlist management) with SVG icons
- Updated upload_media.html with upload-related icons
- Updated manage_player.html with player management icons
- Icons use currentColor for automatic theme adaptation
- Removed emoji dependency for better Raspberry Pi compatibility
- Added ICON_INTEGRATION.md documentation

app/models/group.py

@@ -32,7 +32,6 @@ class Group(db.Model):
                           onupdate=datetime.utcnow, nullable=False)
     
     # Relationships
-    players = db.relationship('Player', back_populates='group', lazy='dynamic')
     contents = db.relationship('Content', secondary=group_content, 
                               back_populates='groups', lazy='dynamic')
     
@@ -40,10 +39,7 @@ class Group(db.Model):
         """String representation of Group."""
         return f'<Group {self.name} (ID={self.id})>'
     
-    @property
-    def player_count(self) -> int:
-        """Get number of players in this group."""
-        return self.players.count()
+
     
     @property
     def content_count(self) -> int: