Refactored docker file

Dockerfile

@@ -1,15 +1,22 @@
-# STAGE 1: Build (Uses the heavy SDK)
+# STAGE 1: Build
 FROM mcr.microsoft.com/dotnet/sdk:8.0 AS build
 WORKDIR /src
-# Copy everything from the solution folder
-COPY . .
-# Publish specifically the project from its subfolder
-RUN [dotnet publish](https://learn.microsoft.com/en-us/dotnet/core/tools/dotnet-publish) "SampleApi/SampleApi.csproj" -c Release -o /app/publish
 
-# STAGE 2: Runtime (Uses the slim ASP.NET image)
+# Copy the solution and all project files to restore dependencies first (better caching)
+COPY . .
+
+# Run publish. 
+# We use --no-self-contained to keep it small since the runtime image has the shared framework.
+RUN dotnet publish "SampleApi/SampleApi.csproj" -c Release -o /app/publish /p:UseAppHost=false
+
+# STAGE 2: Runtime
 FROM mcr.microsoft.com/dotnet/aspnet:8.0
 WORKDIR /app
-# Copy ONLY the compiled binaries from the build stage
+
+# Copy the contents of the publish folder directly into /app
 COPY --from=build /app/publish .
-# The DLL is now in the root of /app, so no folder prefix is needed
+
-ENTRYPOINT ["dotnet", "SampleApi.dll"]
+# Pro-tip: Ensure the port matches your docker-compose
+ENV ASPNETCORE_HTTP_PORTS=8081
+
+ENTRYPOINT ["dotnet", "SampleApi.dll"]