Fix Gradio version compatibility - remove theme parameter

Removed theme=gr.themes.Soft() parameter from gr.Blocks() calls as older Gradio versions don't support it.

src/ui/app.py

@@ -81,7 +81,7 @@ class DnDCampaignManagerApp:
 
     def create_interface(self) -> gr.Blocks:
         """Create and assemble the complete Gradio interface"""
-        with gr.Blocks(title="D'n'D Campaign Manager - Character Creator", theme=gr.themes.Soft()) as interface:
+        with gr.Blocks(title="D'n'D Campaign Manager - Character Creator") as interface:
             gr.Markdown("""
             # 🎲 D'n'D Campaign Manager
             ## Complete D&D Character Creator

src/ui/character_creator_ui.py

@@ -792,7 +792,7 @@ Event has been recorded in campaign history."""
     def create_interface(self) -> gr.Blocks:
         """Create Gradio interface"""
 
-        with gr.Blocks(title="D'n'D Campaign Manager - Character Creator", theme=gr.themes.Soft()) as interface:
+        with gr.Blocks(title="D'n'D Campaign Manager - Character Creator") as interface:
             gr.Markdown("""
             # 🎲 D'n'D Campaign Manager
             ## Complete D&D Character Creator