feat: implement advanced reward management and wheel customization

- Add customizable background color
- Add wheel animations and sound effects
- Add reward description field and winner modal
- Change font to Dana
- Add configurable reward probabilities
- Support reward types (Empty, Discount Code, LiveCoin)
- Replace reward title with reward type selector
- Allow wheel page title customization from admin panel

backend/alembic/versions/eb35214a1411_update_items_table.py

@@ -0,0 +1,28 @@
+"""update items table
+
+Revision ID: eb35214a1411
+Revises: f71dc2bbdfc6
+Create Date: 2026-06-03 02:15:20.584639
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision: str = 'eb35214a1411'
+down_revision: Union[str, Sequence[str], None] = 'f71dc2bbdfc6'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    pass
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    pass

backend/alembic/versions/f71dc2bbdfc6_update_items_table.py

@@ -0,0 +1,28 @@
+"""update items table
+
+Revision ID: f71dc2bbdfc6
+Revises: b55808a86947
+Create Date: 2026-06-03 02:12:35.370477
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision: str = 'f71dc2bbdfc6'
+down_revision: Union[str, Sequence[str], None] = 'b55808a86947'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    pass
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    pass