Add Sonner-based notifications and UX polish

app/root/portfolio/projects/new/page.tsx

@@ -1,7 +1,6 @@
 import { redirect } from "next/navigation";
 
 import { MotionFade } from "@/components/motion-fade";
-import { FlashMessage } from "@/components/root/flash-message";
 import { PortfolioProjectForm } from "@/components/root/portfolio-project-form";
 import { RootDashboardShell } from "@/components/root/root-dashboard-shell";
 import { clearAdminSessionCookie, isAdminAuthenticated } from "@/lib/admin-auth";
@@ -25,15 +24,7 @@ const copy = {
   backToSite: "Zur Website",
 };
 
-type RootNewPortfolioProjectPageProps = {
-  searchParams?: {
-    error?: string;
-  };
-};
-
-export default async function RootNewPortfolioProjectPage({
-  searchParams,
-}: RootNewPortfolioProjectPageProps) {
+export default async function RootNewPortfolioProjectPage() {
   if (!isAdminAuthenticated()) {
     redirect("/root");
   }
@@ -61,12 +52,6 @@ export default async function RootNewPortfolioProjectPage({
       saveFormId="portfolio-project-form"
     >
       <div className="space-y-6">
-        {searchParams?.error ? (
-          <MotionFade delay={0.1}>
-            <FlashMessage type="error" message={searchParams.error} />
-          </MotionFade>
-        ) : null}
-
         <MotionFade delay={0.15}>
           <PortfolioProjectForm
             action={saveProjectAction}