feat: add OpenTelemetry observability, Faro frontend monitoring, remove legacy Next.js app

- Add OpenTelemetry SDK with tracing, metrics, and OTLP export for API and worker
- Integrate Grafana Faro for frontend real-user monitoring
- Instrument health checks, database, Bull queues, and HTTP exception filter
- Add Grafana dashboard JSON for service overview
- Remove deprecated apps/web-nj (Next.js) — fully replaced by Vite+React frontend
- Update nginx config with OTEL collector proxy
- Minor UI fixes in schema viewer, category components, and subscription flow

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

apps/web/src/routes/_auth/login.tsx

@@ -4,6 +4,7 @@ import { Button } from "@sase/ui";
 import { Input } from "@sase/ui";
 import { Label } from "@sase/ui";
 import { signIn } from "@/lib/auth-client";
+import { startAction } from "@/lib/faro";
 import { toast } from "@/lib/toast";
 
 export const Route = createFileRoute("/_auth/login")({
@@ -18,6 +19,7 @@ function LoginPage() {
 
   async function handleSubmit(e: React.FormEvent) {
     e.preventDefault();
+    startAction("login", { method: "email" });
     setLoading(true);
 
     try {
@@ -104,7 +106,10 @@ function LoginPage() {
         <Button
           variant="outline"
           className="w-full"
-          onClick={() => signIn.social({ provider: "google", callbackURL: "/dashboard/search" })}
+          onClick={() => {
+            startAction("login", { method: "google" });
+            signIn.social({ provider: "google", callbackURL: "/dashboard/search" });
+          }}
         >
           Google ile Giriş Yap
         </Button>

apps/web/src/routes/_auth/register.tsx

@@ -4,6 +4,7 @@ import { Button } from "@sase/ui";
 import { Input } from "@sase/ui";
 import { Label } from "@sase/ui";
 import { signIn, signUp } from "@/lib/auth-client";
+import { startAction } from "@/lib/faro";
 import { toast } from "@/lib/toast";
 import { ShieldCheck } from "lucide-react";
 
@@ -19,6 +20,7 @@ function RegisterPage() {
 
   async function handleSubmit(e: React.FormEvent) {
     e.preventDefault();
+    startAction("register", { method: "email" });
     setLoading(true);
 
     try {
@@ -107,7 +109,10 @@ function RegisterPage() {
         <Button
           variant="outline"
           className="w-full"
-          onClick={() => signIn.social({ provider: "google", callbackURL: "/dashboard/subscription?welcome=1" })}
+          onClick={() => {
+            startAction("register", { method: "google" });
+            signIn.social({ provider: "google", callbackURL: "/dashboard/subscription?welcome=1" });
+          }}
         >
           Google ile Kayıt Ol
         </Button>