Fix website build and 0.8.x pages, move deploy to workflow and nixify the website part (#982)

nix/website-build.nix

@@ -0,0 +1,21 @@
+{ pkgs, system, hugo_099_pkgs }:
+
+let
+  buildPackages = [
+    hugo_099_pkgs.hugo #hugo pre-v100
+    pkgs.nodejs_21 #Node 1.21
+    pkgs.nodePackages.autoprefixer
+    pkgs.nodePackages.postcss
+    pkgs.nodePackages.postcss-cli
+  ];
+  baseUrl = ((builtins.fromTOML (builtins.readFile ../website/config.toml)).baseURL);
+in
+pkgs.buildNpmPackage {
+  name = "jenkins-kubernetes-operator-website";
+  src = ../website;
+  version = "0.0.1";
+  npmDepsHash = "sha256-NcspVYF+9dCrGxH/cGNhD+TxLZm6ZDX523mKm9smAAA=";
+  nativeBuildInputs = buildPackages;
+  buildPhase = "npm run build";
+  installPhase = "cp -r public $out";
+}

nix/website-shell.nix

@@ -0,0 +1,17 @@
+{ pkgs, system, hugo_099_pkgs }:
+
+let
+  devShellPackages = [
+    hugo_099_pkgs.hugo #hugo pre-v100
+    pkgs.nodejs_21 #Node 1.21
+  ];
+  baseUrl = ((builtins.fromTOML (builtins.readFile ../website/config.toml)).baseURL);
+in
+pkgs.mkShell {
+  packages = devShellPackages;
+  shellHook = ''
+    npm install --save-dev
+    npm list
+  '';
+  BASE_URL = "${baseUrl}";
+}