feat: admin panel with SQLite, auth, and calendar-style schedule editor

Complete admin panel for content management:
- SQLite database with better-sqlite3, seed script from content.ts
- Simple password auth with HMAC-signed cookies (Edge + Node compatible)
- 9 section editors: meta, hero, about, team, classes, schedule, pricing, FAQ, contact
- Team CRUD with image upload and drag reorder
- Schedule editor with Google Calendar-style visual timeline (colored blocks, overlap detection, click-to-add)
- All public components refactored to accept data props from DB (with fallback to static content)
- Middleware protecting /admin/* and /api/admin/* routes

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

src/components/sections/Hero.tsx

@@ -1,13 +1,16 @@
 "use client";
 
-import { siteContent } from "@/data/content";
 import { Button } from "@/components/ui/Button";
 import { FloatingHearts } from "@/components/ui/FloatingHearts";
 import { HeroLogo } from "@/components/ui/HeroLogo";
 import { ChevronDown } from "lucide-react";
+import type { SiteContent } from "@/types/content";
 
-export function Hero() {
-  const { hero } = siteContent;
+interface HeroProps {
+  data: SiteContent["hero"];
+}
+
+export function Hero({ data: hero }: HeroProps) {
 
   return (
     <section className="relative flex min-h-svh items-center justify-center overflow-hidden bg-[#050505]">