adding hidden basic asp.net core backend (#30)

Base functionality:

    DB
    email sending
    user registration & login
    storing new characters and reading them back

Notes:

    Functionality is "hidden" with no links pointing to it.
    Most pages are scaffolded and not reviewed at all :(
    local Dev db setup is pushed to git
    NO local email setup :(

Kemkas.Web/Dockerfile

@@ -1,16 +1,9 @@
-FROM mcr.microsoft.com/dotnet/aspnet:7.0 AS base
+FROM mcr.microsoft.com/dotnet/aspnet:8.0 AS base
 WORKDIR /app
 EXPOSE 80
 EXPOSE 443
 
-FROM mcr.microsoft.com/dotnet/sdk:7.0 AS build
-
-# Install Node.js
-RUN curl -fsSL https://deb.nodesource.com/setup_18.x | bash - \
-    && apt-get install -y nodejs \
-    && npm install --global yarn \
-    && rm -rf /var/lib/apt/lists/*
-
+FROM mcr.microsoft.com/dotnet/sdk:8.0 AS build
 WORKDIR /src
 COPY ["Kemkas.Web/Kemkas.Web.csproj", "Kemkas.Web/"]
 RUN dotnet restore "Kemkas.Web/Kemkas.Web.csproj"
@@ -21,7 +14,16 @@ RUN dotnet build "Kemkas.Web.csproj" -c Release -o /app/build
 FROM build AS publish
 RUN dotnet publish "Kemkas.Web.csproj" -c Release -o /app/publish /p:UseAppHost=false
 
+FROM node:21.4-bookworm AS frontend
+WORKDIR /src
+COPY ["Kemkas.Web/frontend/package.json", "Kemkas.Web/frontend/yarn.lock", "./"]
+RUN yarn install --frozen-lockfile
+COPY ["Kemkas.Web/frontend/", "./"]
+RUN bash compile-less.sh
+RUN yarn run build
+
 FROM base AS final
 WORKDIR /app
 COPY --from=publish /app/publish .
+COPY --from=frontend /src/build ./wwwroot
 ENTRYPOINT ["dotnet", "Kemkas.Web.dll"]