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/app/admin/faq/page.tsx

@@ -0,0 +1,48 @@
+"use client";
+
+import { SectionEditor } from "../_components/SectionEditor";
+import { InputField, TextareaField } from "../_components/FormField";
+import { ArrayEditor } from "../_components/ArrayEditor";
+
+interface FAQData {
+  title: string;
+  items: { question: string; answer: string }[];
+}
+
+export default function FAQEditorPage() {
+  return (
+    <SectionEditor<FAQData> sectionKey="faq" title="FAQ">
+      {(data, update) => (
+        <>
+          <InputField
+            label="Заголовок секции"
+            value={data.title}
+            onChange={(v) => update({ ...data, title: v })}
+          />
+          <ArrayEditor
+            label="Вопросы и ответы"
+            items={data.items}
+            onChange={(items) => update({ ...data, items })}
+            renderItem={(item, _i, updateItem) => (
+              <div className="space-y-3">
+                <InputField
+                  label="Вопрос"
+                  value={item.question}
+                  onChange={(v) => updateItem({ ...item, question: v })}
+                />
+                <TextareaField
+                  label="Ответ"
+                  value={item.answer}
+                  onChange={(v) => updateItem({ ...item, answer: v })}
+                  rows={3}
+                />
+              </div>
+            )}
+            createItem={() => ({ question: "", answer: "" })}
+            addLabel="Добавить вопрос"
+          />
+        </>
+      )}
+    </SectionEditor>
+  );
+}