Fix: Revert to aspnet runtime for Blazor Server with gRPC

src/BackOffice/Dockerfile

@@ -1,3 +1,7 @@
+FROM mcr.microsoft.com/dotnet/aspnet:9.0 AS base
+WORKDIR /app
+EXPOSE 8080
+
 FROM mcr.microsoft.com/dotnet/sdk:9.0 AS build
 WORKDIR /src
 COPY ["BackOffice/NuGet.config", "NuGet.config"]
@@ -5,20 +9,14 @@ COPY ["BackOffice/BackOffice.csproj", "BackOffice/"]
 RUN dotnet restore "BackOffice/BackOffice.csproj" --configfile NuGet.config
 COPY . .
 WORKDIR "/src/BackOffice"
-RUN dotnet publish "./BackOffice.csproj" -c Release -o /app/publish
+RUN dotnet build "./BackOffice.csproj" -c Release -o /app/build
 
-FROM nginx:alpine AS final
-WORKDIR /usr/share/nginx/html
-COPY --from=build /app/publish/wwwroot .
-COPY <<'NGINX_CONF' /etc/nginx/conf.d/default.conf
-server {
-    listen 80;
-    server_name _;
+FROM build AS publish
+RUN dotnet publish "./BackOffice.csproj" -c Release -o /app/publish /p:UseAppHost=false
 
-    location / {
-        root /usr/share/nginx/html;
-        try_files $uri $uri/ /index.html;
-    }
-}
-NGINX_CONF
-EXPOSE 80
+FROM base AS final
+WORKDIR /app
+COPY --from=publish /app/publish .
+
+ENV ASPNETCORE_URLS=http://+:8080
+ENTRYPOINT ["dotnet", "BackOffice.dll"]