feat: add svelte

the functionality for a svelte package
isn't here yet though :(

templates/svelte/flake.nix

@@ -0,0 +1,31 @@
+{
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-24.05";
+  };
+
+  outputs =
+    { nixpkgs, ... }:
+    let
+      lib = nixpkgs.lib;
+      systems = [
+        "x86_64-linux"
+        "aarch64-linux"
+      ];
+      forAllSystems = f: lib.genAttrs systems (system: f { pkgs = nixpkgs.legacyPackages.${system}; });
+    in
+    {
+      formatter = forAllSystems ({ pkgs }: pkgs.nixfmt-rfc-style);
+      devShells = forAllSystems (
+        { pkgs }:
+        {
+          default = pkgs.callPackage ./flake/devshell.nix { };
+        }
+      );
+      packages = forAllSystems (
+        { pkgs }:
+        {
+          svelte-example = pkgs.callPackage ./flake/derivation.nix { };
+        }
+      );
+    };
+}