perf: remove TipTap/ProseMirror from client bundle, lazy-load below-fold sections

TipTap (ProseMirror) was causing:
- chunks 1007 (85 KiB) and 3207 (58 KiB) in the initial bundle
- Array.prototype.at/flat/flatMap, Object.fromEntries/hasOwn polyfills
  (ProseMirror bundles core-js for these — the 12 KiB legacy JS flag)
- 2+ seconds of main thread blocking on mobile

Fix: move HTML conversion to the server (API route) and pass the
resulting HTML string to the client, eliminating the need to import
richTextToSafeHtml (and transitively TipTap) in any client component.

Changes:
- app/api/content/page/route.ts: call richTextToSafeHtml server-side,
  add html: string to response alongside existing content
- app/components/RichTextClient.tsx: accept html string, remove all
  TipTap imports — TipTap/ProseMirror now has zero client bundle cost
- app/components/About.tsx, Contact.tsx: use cmsHtml from API
- app/legal-notice/page.tsx, privacy-policy/page.tsx: same
- app/components/ClientWrappers.tsx: change static imports of About,
  Projects, Contact, Footer to next/dynamic so their JS is in
  separate lazy-loaded chunks, not in the initial bundle

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/components/About.tsx

@@ -3,7 +3,6 @@
 import { useState, useEffect } from "react";
 import { Globe, Server, Wrench, Shield, Gamepad2, Code, Activity, Lightbulb, BookOpen, MessageSquare, ArrowRight, Tv, Plane, Camera, Stars, Music, Terminal, Cpu } from "lucide-react";
 import { useLocale, useTranslations } from "next-intl";
-import type { JSONContent } from "@tiptap/react";
 import dynamic from "next/dynamic";
 const RichTextClient = dynamic(() => import("./RichTextClient"), { ssr: false });
 import CurrentlyReading from "./CurrentlyReading";
@@ -23,7 +22,7 @@ const iconMap: Record<string, LucideIcon> = {
 const About = () => {
   const locale = useLocale();
   const t = useTranslations("home.about");
-  const [cmsDoc, setCmsDoc] = useState<JSONContent | null>(null);
+  const [cmsHtml, setCmsHtml] = useState<string | null>(null);
   const [techStack, setTechStack] = useState<TechStackCategory[]>([]);
   const [hobbies, setHobbies] = useState<Hobby[]>([]);
   const [snippets, setSnippets] = useState<Snippet[]>([]);
@@ -44,7 +43,7 @@ const About = () => {
         ]);
         
         const cmsData = await cmsRes.json();
-        if (cmsData?.content?.content) setCmsDoc(cmsData.content.content as JSONContent);
+        if (cmsData?.content?.html) setCmsHtml(cmsData.content.html as string);
         
         const techData = await techRes.json();
         if (techData?.techStack) setTechStack(techData.techStack);
@@ -93,8 +92,8 @@ const About = () => {
                     <Skeleton className="h-6 w-[95%]" />
                     <Skeleton className="h-6 w-[90%]" />
                   </div>
-                ) : cmsDoc ? (
-                  <RichTextClient doc={cmsDoc} />
+                ) : cmsHtml ? (
+                  <RichTextClient html={cmsHtml} />
                 ) : (
                   <p>{t("p1")} {t("p2")}</p>
                 )}

app/components/ClientWrappers.tsx

@@ -6,10 +6,14 @@
  */
 
 import { NextIntlClientProvider } from 'next-intl';
-import About from './About';
-import Projects from './Projects';
-import Contact from './Contact';
-import Footer from './Footer';
+import dynamic from 'next/dynamic';
+
+// Lazy-load below-fold components so their JS doesn't block initial paint / LCP.
+// SSR stays on (default) so content is in the initial HTML for SEO.
+const About = dynamic(() => import('./About'));
+const Projects = dynamic(() => import('./Projects'));
+const Contact = dynamic(() => import('./Contact'));
+const Footer = dynamic(() => import('./Footer'));
 import type {
   AboutTranslations,
   ProjectsTranslations,

app/components/Contact.tsx

@@ -5,7 +5,6 @@ import { motion } from "framer-motion";
 import { Mail, MapPin, Send, Github, Linkedin } from "lucide-react";
 import { useToast } from "@/components/Toast";
 import { useLocale, useTranslations } from "next-intl";
-import type { JSONContent } from "@tiptap/react";
 import dynamic from "next/dynamic";
 const RichTextClient = dynamic(() => import("./RichTextClient"), { ssr: false });
 
@@ -15,7 +14,7 @@ const Contact = () => {
   const t = useTranslations("home.contact");
   const tForm = useTranslations("home.contact.form");
   const tInfo = useTranslations("home.contact.info");
-  const [cmsDoc, setCmsDoc] = useState<JSONContent | null>(null);
+  const [cmsHtml, setCmsHtml] = useState<string | null>(null);
 
   useEffect(() => {
     (async () => {
@@ -25,14 +24,14 @@ const Contact = () => {
         );
         const data = await res.json();
         // Only use CMS content if it exists for the active locale.
-        if (data?.content?.content && data?.content?.locale === locale) {
-          setCmsDoc(data.content.content as JSONContent);
+        if (data?.content?.html && data?.content?.locale === locale) {
+          setCmsHtml(data.content.html as string);
         } else {
-          setCmsDoc(null);
+          setCmsHtml(null);
         }
       } catch {
         // ignore; fallback to static
-        setCmsDoc(null);
+        setCmsHtml(null);
       }
     })();
   }, [locale]);
@@ -169,8 +168,8 @@ const Contact = () => {
               <h2 className="text-3xl sm:text-4xl md:text-5xl lg:text-7xl font-black text-stone-900 dark:text-stone-50 tracking-tighter uppercase mb-4 sm:mb-6 md:mb-8">
                 {t("title")}<span className="text-emerald-600 dark:text-emerald-400">.</span>
               </h2>
-              {cmsDoc ? (
-                <RichTextClient doc={cmsDoc} className="prose prose-stone dark:prose-invert max-w-none text-base sm:text-lg md:text-xl lg:text-2xl font-light leading-relaxed text-stone-600 dark:text-stone-400" />
+              {cmsHtml ? (
+                <RichTextClient html={cmsHtml} className="prose prose-stone dark:prose-invert max-w-none text-base sm:text-lg md:text-xl lg:text-2xl font-light leading-relaxed text-stone-600 dark:text-stone-400" />
               ) : (
                 <p className="text-base sm:text-lg md:text-xl lg:text-2xl font-light leading-relaxed text-stone-600 dark:text-stone-400">
                   {t("subtitle")}

app/components/RichTextClient.tsx

@@ -1,22 +1,19 @@
 "use client";
 
-import React, { useMemo } from "react";
-import type { JSONContent } from "@tiptap/react";
-import { richTextToSafeHtml } from "@/lib/richtext";
+import React from "react";
 
+// Accepts pre-sanitized HTML string (converted server-side via richTextToSafeHtml).
+// This keeps TipTap/ProseMirror out of the client bundle entirely.
 export default function RichTextClient({
-  doc,
+  html,
   className,
 }: {
-  doc: JSONContent;
+  html: string;
   className?: string;
 }) {
-  const html = useMemo(() => richTextToSafeHtml(doc), [doc]);
-
   return (
     <div
       className={className}
-      // HTML is sanitized in `richTextToSafeHtml`
       dangerouslySetInnerHTML={{ __html: html }}
     />
   );