fix: build and test stability for design overhaul

Fixed missing types, import errors, and updated test suites to match the new editorial design. Verified Docker container build.

app/_ui/ProjectsPageClient.tsx

@@ -4,7 +4,7 @@ import { useEffect, useMemo, useState } from "react";
 import { motion } from "framer-motion";
 import { ArrowUpRight, ArrowLeft, Search } from "lucide-react";
 import Link from "next/link";
-import { useLocale, useTranslations } from "next-intl";
+import { useTranslations } from "next-intl";
 import Image from "next/image";
 import { Skeleton } from "../components/ui/Skeleton";
 
@@ -15,7 +15,7 @@ export type ProjectListItem = {
   description: string;
   tags: string[];
   category: string;
-  date: string;
+  date?: string;
   imageUrl?: string | null;
 };