Redesign marketing pages and isolate public routes from app auth.

Give the landing, legal, and sign-in flows a consistent product shell while keeping marketing pages free of tRPC/session calls, fixing dev auth URL handling, and refreshing env and deploy docs.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/components/providers/app-providers.tsx

@@ -0,0 +1,18 @@
+"use client";
+
+import { AnimationPreferencesProviderSynced } from "~/components/providers/animation-preferences-provider-synced";
+import { AppearanceProviderSynced } from "~/components/providers/appearance-provider-synced";
+import { TRPCReactProvider } from "~/trpc/react";
+
+/** Full app providers for authenticated workspace routes. */
+export function AppProviders({ children }: { children: React.ReactNode }) {
+  return (
+    <TRPCReactProvider>
+      <AppearanceProviderSynced>
+        <AnimationPreferencesProviderSynced>
+          {children}
+        </AnimationPreferencesProviderSynced>
+      </AppearanceProviderSynced>
+    </TRPCReactProvider>
+  );
+}