feat: Cloudflare Turnstile on auth, CSP fixes, admin/SEO/analytics additions

Turnstile bot protection (sign-in, sign-up, password-reset):
- Register Better Auth's captcha plugin with the cloudflare-turnstile
  provider; endpoints listed explicitly rather than relying on defaults.
  /reset-password is intentionally excluded — it is reached only via a
  single-use emailed token.
- Add an explicit-render Turnstile widget component. Tokens are single-use,
  so each form resets the challenge after a failed submit; submit stays
  disabled until a token is held.
- Read the site key server-side and pass it down as a prop, so rotating it
  does not require a rebuild.
- Fail fast in production when TURNSTILE_SECRET_KEY is missing, and when a
  secret is set without a site key (that combination would demand a token
  no form can produce, locking every user out).
- Pass a throwaway secret during `next build` in the Dockerfile, mirroring
  the existing BETTER_AUTH_SECRET treatment, so image builds don't need it.

CSP fixes in middleware (these blocked Turnstile entirely):
- Add frame-src for challenges.cloudflare.com. Without it the widget's
  iframe fell back to default-src 'self' and was blocked outright.
- Allow 'unsafe-eval' and websockets in DEVELOPMENT only. `next dev`
  compiles with eval(), so the strict policy threw EvalError and killed
  hydration — no client JS ran at all, which also meant form submit
  handlers never fired. Production policy is unchanged and still strict.

Also included (concurrent work in the tree):
- Admin organizations pages and lib/admin/orgs.
- Episode moderation migration, SEO metadata (sitemap, robots, JSON-LD,
  OG/Twitter images, manifest), Umami analytics, not-found page.

Local dev database: docker-compose.dev.yml provisions Postgres 18 on port
5443 (5432-5442 are in use by other local projects).

Note: `npx tsc --noEmit` currently fails in app/(app)/team/page.tsx — an
`invitations` prop the component does not accept. This predates the commit
and will fail `next build` until fixed.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

app/(marketing)/faq/page.tsx

@@ -2,12 +2,19 @@ import type { Metadata } from "next";
 import Link from "next/link";
 import { ChevronDown, ArrowRight } from "lucide-react";
 import { Button } from "@/components/ui/button";
+import { JsonLd } from "@/components/seo/json-ld";
+import { breadcrumbSchema, faqPageSchema, graph, webPageSchema } from "@/lib/schema";
+import { pageMetadata } from "@/lib/seo";
 
-export const metadata: Metadata = {
+/** Shared by the page metadata and this page's structured data. */
+const DESCRIPTION =
+  "Answers to common questions about creating AI podcasts with Podcast Distribution AI — generation, voices, languages, plans, billing, repurposing, the API, and teams.";
+
+export const metadata: Metadata = pageMetadata({
   title: "FAQ",
-  description:
-    "Answers to common questions about creating AI podcasts with Podcast Distribution AI — generation, voices, languages, plans, billing, repurposing, the API, and teams.",
-};
+  description: DESCRIPTION,
+  path: "/faq",
+});
 
 interface QA {
   q: string;
@@ -129,6 +136,14 @@ const FAQ: Category[] = [
 export default function FaqPage() {
   return (
     <div className="bg-hero-wash">
+      <JsonLd
+        data={graph(
+          webPageSchema({ path: "/faq", name: "FAQ", description: DESCRIPTION }),
+          breadcrumbSchema([{ name: "FAQ", path: "/faq" }]),
+          // Flattened across categories — FAQPage takes one list of questions.
+          faqPageSchema(FAQ.flatMap((category) => category.items))
+        )}
+      />
       <div className="container max-w-3xl py-20 md:py-28">
         <div className="text-center">
           <p className="text-[13px] font-semibold uppercase tracking-[0.04em] text-brand">Support</p>