feat: organizers, meetups UI, Plausible analytics, and migration tooling

- Add organizer model/API, admin and public organizer pages, meetup cards
- Refresh events/home/contact; add calendar dialog and carousel components
- Optional Plausible via NEXT_PUBLIC_PLAUSIBLE_* env vars in root layout
- Prisma migration, seed updates, baseline-and-migrate script

Made-with: Cursor

frontend/components/public/UpcomingEventsCarousel.tsx

@@ -0,0 +1,80 @@
+"use client";
+
+import { useEffect, useRef, useState } from "react";
+import { ChevronLeft, ChevronRight } from "lucide-react";
+import { api } from "@/lib/api";
+import { getMeetupStartUtc } from "@/lib/meetupEventTime";
+import { MeetupCard } from "@/components/public/MeetupCard";
+
+export function UpcomingEventsCarousel({ excludeId }: { excludeId: string }) {
+  const [items, setItems] = useState<any[]>([]);
+  const scrollerRef = useRef<HTMLDivElement>(null);
+
+  useEffect(() => {
+    api
+      .getMeetups()
+      .then((data: any) => {
+        const list = Array.isArray(data) ? data : [];
+        const now = new Date();
+        const upcoming = list
+          .filter((m: any) => {
+            if (m.id === excludeId) return false;
+            const start = getMeetupStartUtc(m.date, m.time || "00:00");
+            if (Number.isNaN(start.getTime())) return false;
+            return start >= now;
+          })
+          .sort(
+            (a: any, b: any) =>
+              getMeetupStartUtc(a.date, a.time || "00:00").getTime() -
+              getMeetupStartUtc(b.date, b.time || "00:00").getTime()
+          );
+        setItems(upcoming);
+      })
+      .catch(() => setItems([]));
+  }, [excludeId]);
+
+  const scrollByDir = (dir: -1 | 1) => {
+    const el = scrollerRef.current;
+    if (!el) return;
+    const delta = Math.min(el.clientWidth * 0.85, 360);
+    el.scrollBy({ left: dir * delta, behavior: "smooth" });
+  };
+
+  if (items.length === 0) return null;
+
+  return (
+    <section className="mt-16 pt-12 border-t border-zinc-800/50">
+      <div className="flex items-end justify-between gap-4 mb-6">
+        <h2 className="text-lg font-black tracking-tight">More upcoming events</h2>
+        <div className="flex gap-2 shrink-0">
+          <button
+            type="button"
+            onClick={() => scrollByDir(-1)}
+            className="p-2.5 rounded-xl border border-zinc-800 bg-zinc-900/80 text-on-surface-variant hover:text-primary hover:border-zinc-700 transition-colors"
+            aria-label="Scroll left"
+          >
+            <ChevronLeft size={18} />
+          </button>
+          <button
+            type="button"
+            onClick={() => scrollByDir(1)}
+            className="p-2.5 rounded-xl border border-zinc-800 bg-zinc-900/80 text-on-surface-variant hover:text-primary hover:border-zinc-700 transition-colors"
+            aria-label="Scroll right"
+          >
+            <ChevronRight size={18} />
+          </button>
+        </div>
+      </div>
+      <div
+        ref={scrollerRef}
+        className="flex gap-4 overflow-x-auto scroll-smooth snap-x snap-mandatory pb-2 -mx-1 px-1 [scrollbar-width:thin]"
+      >
+        {items.map((m) => (
+          <div key={m.id} className="snap-start shrink-0 w-[min(280px,calc(100vw-5rem))] sm:w-[280px]">
+            <MeetupCard meetup={m} />
+          </div>
+        ))}
+      </div>
+    </section>
+  );
+}