Build new nix {module,package,flake}. Adapt to new config variables

Co-authored-by: h7x4 <h7x4@nani.wtf>

nix/shell.nix

@@ -0,0 +1,35 @@
+{ pkgs }:
+let
+  phpEnv = pkgs.php82.buildEnv {
+    extensions = { enabled, all }: enabled ++ (with all; [ iconv mbstring pdo_mysql pdo_sqlite ]);
+  };
+in
+pkgs.mkShellNoCC {
+  buildInputs = with pkgs; [
+    phpEnv
+    php82Packages.composer
+
+    sqlite
+    git
+  ];
+  shellHook = ''
+    alias runDev='php -S localhost:1080 -d error_reporting=E_ALL -d display_errors=1 -t www/'
+
+    # Prepare dev environment with sqlite and config files
+    test -e pvv.sqlite || sqlite3 pvv.sqlite < dist/pvv.sql
+    test -e config.php || cp -v dist/config.local.php config.php
+
+
+    if [ ! -d vendor ] ; then
+      composer install || exit $?
+
+      cp dist/simplesamlphp-authsources.php vendor/simplesamlphp/simplesamlphp/config/authsources.php
+      cp dist/simplesamlphp-idp.php vendor/simplesamlphp/simplesamlphp/metadata/saml20-idp-remote.php
+      cp dist/simplesamlphp-config.php vendor/simplesamlphp/simplesamlphp/config/config.php
+
+      cp dist/config.local.php config.php
+
+      ln -s ../vendor/simplesamlphp/simplesamlphp/www/ www/simplesaml
+    fi
+  '';
+}