svelte: isolate prettier formatter wiring and fix plugin runtime packaging

flake/pkgs/by-name/prettier-plugin-svelte/package.nix

@@ -1,6 +1,8 @@
 {
   buildNpmPackage,
   fetchFromGitHub,
+  makeWrapper,
+  nodejs,
   pins,
 }: let
   pin = pins.prettier-plugin-svelte;
@@ -9,6 +11,8 @@ in
     pname = "prettier-plugin-svelte";
     version = pin.version or pin.revision;
 
+    meta.mainProgram = "prettier";
+
     src = fetchFromGitHub {
       inherit (pin.repository) owner repo;
       rev = finalAttrs.version;
@@ -16,4 +20,21 @@ in
     };
 
     npmDepsHash = "sha256-XVyLW0XDCvZCZxu8g1fP7fRfeU3Hz81o5FCi/i4BKQw=";
+
+    nativeBuildInputs = [makeWrapper];
+
+    installPhase = ''
+      runHook preInstall
+
+      mkdir -p "$out/bin" "$out/lib"
+      cp -r node_modules "$out/lib/"
+      mkdir -p "$out/lib/node_modules/prettier-plugin-svelte"
+      cp -r browser.js index.d.ts package.json plugin.js plugin.js.map "$out/lib/node_modules/prettier-plugin-svelte/"
+
+      makeWrapper "${nodejs}/bin/node" "$out/bin/prettier" \
+        --add-flags "$out/lib/node_modules/prettier/bin/prettier.cjs" \
+        --set NODE_PATH "$out/lib/node_modules"
+
+      runHook postInstall
+    '';
   })