fix: restore glitchtip nesting and fix type errors

lib/config.ts

@@ -36,12 +36,14 @@ function createConfig() {
     },
 
     errors: {
+      glitchtip: {
         // Use NEXT_PUBLIC_SENTRY_DSN if available (required for browser-side SDK)
-        dsn: env.NEXT_PUBLIC_SENTRY_DSN || (env as any).SENTRY_DSN,
+        dsn: env.NEXT_PUBLIC_SENTRY_DSN || env.SENTRY_DSN,
         // The proxied origin used in the frontend
         proxyPath: "/errors",
         enabled: Boolean(env.SENTRY_DSN),
       },
+    },
 
     cache: {
       enabled: false,

lib/env.ts

@@ -18,6 +18,7 @@ const envExtension = {
   // Project specific overrides or additions
   AUTH_COOKIE_NAME: z.string().default("mb_gatekeeper_session"),
   NEXT_PUBLIC_SENTRY_DSN: z.string().optional(),
+  SENTRY_DSN: z.string().optional(),
 };
 
 /**