fix gradio version in Dockerfile

Dockerfile

@@ -23,7 +23,7 @@ COPY requirements.txt .
 # Fresh install of Gradio 6 as recommended by Gradio team
 # Install in a single command to avoid conflicts
 RUN pip install --no-cache-dir --upgrade pip && \
-    pip install --no-cache-dir "gradio[mcp,oauth]==5.49.1" && \
+    pip install --no-cache-dir "gradio[mcp,oauth]==5.50.0" && \
     pip install --no-cache-dir -r requirements.txt
 
 # Copy application code