refactor: Standardize Umami analytics environment variables to non-public names with fallbacks to NEXT_PUBLIC_ prefixed versions.

lib/config.ts

@@ -27,11 +27,9 @@ function createConfig() {
 
     analytics: {
       umami: {
-        websiteId: env.NEXT_PUBLIC_UMAMI_WEBSITE_ID,
-        scriptUrl: env.NEXT_PUBLIC_UMAMI_SCRIPT_URL,
-        // The proxied path used in the frontend
-        proxyPath: '/stats/script.js',
-        enabled: Boolean(env.NEXT_PUBLIC_UMAMI_WEBSITE_ID),
+        websiteId: env.UMAMI_WEBSITE_ID,
+        apiEndpoint: env.UMAMI_API_ENDPOINT,
+        enabled: Boolean(env.UMAMI_WEBSITE_ID),
       },
     },
 
@@ -152,7 +150,7 @@ export function getMaskedConfig() {
     analytics: {
       umami: {
         websiteId: mask(c.analytics.umami.websiteId),
-        scriptUrl: c.analytics.umami.scriptUrl,
+        apiEndpoint: c.analytics.umami.apiEndpoint,
         enabled: c.analytics.umami.enabled,
       },
     },