Add Analytics package (#46)

* Add Analytics package

Created a new analytics package with a manager to handle tracking of events and page views. The package includes a default provider that can be switched out and uses a NullAnalyticsService if no provider is registered. Additional types, scripts, and package configuration are also provided to support development.

* Add marketing components for UI package

Introduced new React components under "marketing" for the UI package. These include 'Pill', 'GradientSecondaryText', 'Hero', 'CtaButton', 'FeatureCard', 'FeatureGrid', 'FeatureShowcase', 'GradientText', 'Header', and 'SecondaryHero'. Updated 'package.json' to export these components. Replaced the implementation of 'Home', 'SiteHeader', and 'SiteFooter' with these components for cleaner code and better reusability.

apps/web/app/(marketing)/_components/site-header.tsx

@@ -1,5 +1,7 @@
 import type { User } from '@supabase/supabase-js';
 
+import { Header } from '@kit/ui/marketing';
+
 import { AppLogo } from '~/components/app-logo';
 
 import { SiteHeaderAccountSection } from './site-header-account-section';
@@ -7,26 +9,10 @@ import { SiteNavigation } from './site-navigation';
 
 export function SiteHeader(props: { user?: User | null }) {
   return (
-    <div
-      className={
-        'site-header sticky top-0 z-10 w-full bg-background/80 py-2 backdrop-blur-md dark:bg-background/50'
-      }
-    >
-      <div className={'container'}>
-        <div className="grid h-14 grid-cols-3 items-center">
-          <div>
-            <AppLogo />
-          </div>
-
-          <div className={'order-first md:order-none'}>
-            <SiteNavigation />
-          </div>
-
-          <div className={'flex items-center justify-end space-x-1'}>
-            <SiteHeaderAccountSection user={props.user ?? null} />
-          </div>
-        </div>
-      </div>
-    </div>
+    <Header
+      logo={<AppLogo />}
+      navigation={<SiteNavigation />}
+      actions={<SiteHeaderAccountSection user={props.user ?? null} />}
+    />
   );
 }