Update admin theme/layout and refresh README details.

Align the project baseline with the latest admin interface styling and layout structure while documenting setup and usage updates in README.

apps/api/app/modules/test/router.py

@@ -0,0 +1,16 @@
+from fastapi import APIRouter, HTTPException, Query
+
+from app.core.config import settings
+from app.core.email import memory_mailer
+
+router = APIRouter()
+
+
+@router.get("/emails/latest-token")
+async def latest_email_token(to: str = Query(...), template: str = Query(...)):
+    if not settings.enable_test_routes or settings.email_delivery_mode != "memory":
+        raise HTTPException(status_code=404, detail="NOT_FOUND")
+    token = memory_mailer.latest_token(to, template)
+    if not token:
+        raise HTTPException(status_code=404, detail="TOKEN_NOT_FOUND")
+    return {"token": token}