feat(analytics): implement advanced tracking with script-less smart proxy

- Added Umami Smart Proxy route handler
- Refactored Umami adapter to use proxy-based fetch
- Implemented TrackedButton, TrackedLink, and ScrollDepthTracker
- Integrated event tracking into ContactForm
- Enhanced Analytics component with manual pageview and performance tracking

apps/web/src/lib/env.ts

@@ -12,6 +12,14 @@ const envExtension = {
   MAIL_PASS: z.string().optional(),
   MAIL_FROM: z.string().optional().default("marc@mintel.me"),
   MAIL_RECIPIENTS: z.string().optional().default("marc@mintel.me"),
+
+  // Analytics (Server-side)
+  UMAMI_WEBSITE_ID: z.string().optional(),
+  UMAMI_API_ENDPOINT: z
+    .string()
+    .url()
+    .optional()
+    .default("https://analytics.infra.mintel.me"),
 };
 
 /**