Added dockerfile.

JSMR.Api/Dockerfile

@@ -0,0 +1,24 @@
+# --- Build stage ---
+FROM mcr.microsoft.com/dotnet/sdk:9.0 AS build
+WORKDIR /src
+
+# copy solution + restore-friendly files first for better layer caching
+COPY JSMR.sln ./
+COPY src/JSMR.Api/JSMR.Api.csproj src/JSMR.Api/
+COPY src/JSMR.Application/JSMR.Application.csproj src/JSMR.Application/
+COPY src/JSMR.Domain/JSMR.Domain.csproj src/JSMR.Domain/
+COPY src/JSMR.Infrastructure/JSMR.Infrastructure.csproj src/JSMR.Infrastructure/
+RUN dotnet restore src/JSMR.Api/JSMR.Api.csproj
+
+# now copy the rest and publish
+COPY src/ ./src/
+RUN dotnet publish src/JSMR.Api/JSMR.Api.csproj -c Release -o /app/publish --no-restore
+
+# --- Runtime stage ---
+FROM mcr.microsoft.com/dotnet/aspnet:9.0 AS runtime
+WORKDIR /app
+COPY --from=build /app/publish ./
+# optional: set ASPNETCORE_URLS to port 8080
+ENV ASPNETCORE_URLS=http://+:8080
+EXPOSE 8080
+ENTRYPOINT ["dotnet", "JSMR.Api.dll"]