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.

packages/ui/src/makerkit/marketing/secondary-hero.tsx

@@ -0,0 +1,49 @@
+import { forwardRef } from 'react';
+
+import { Heading } from '../../shadcn/heading';
+import { cn } from '../../utils';
+
+interface SecondaryHeroProps extends React.HTMLAttributes<HTMLDivElement> {
+  pill?: React.ReactNode;
+  heading: React.ReactNode;
+  subheading: React.ReactNode;
+}
+
+export const SecondaryHero = forwardRef<HTMLDivElement, SecondaryHeroProps>(
+  function SecondaryHeroComponent(
+    { className, pill, heading, subheading, children, ...props },
+    ref,
+  ) {
+    return (
+      <div
+        ref={ref}
+        className={cn(
+          'flex flex-col items-center space-y-4 text-center',
+          className,
+        )}
+        {...props}
+      >
+        {pill && (
+          <div className="delay-300 duration-700 animate-in fade-in">
+            {pill}
+          </div>
+        )}
+
+        <div className="flex flex-col">
+          <Heading level={2} className="tracking-tighter">
+            {heading}
+          </Heading>
+
+          <Heading
+            level={3}
+            className="font-sans font-normal tracking-tight text-muted-foreground"
+          >
+            {subheading}
+          </Heading>
+        </div>
+
+        {children}
+      </div>
+    );
+  },
+);