feat: access extension — NFC door access via boltcards SUN + Home Assistant

Promoted from the door-portal scratch repo to its own repo for install via the
aiolabs catalog. Authenticates a tapped Bolt Card via boltcards /verify,
authorizes against per-door grants, and fires the door's local Home Assistant
webhook to unlock a Z-Wave lock. Fails closed; logs every attempt.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

views.py

@@ -0,0 +1,18 @@
+from fastapi import APIRouter, Depends, Request
+from fastapi.responses import HTMLResponse
+from lnbits.core.models import User
+from lnbits.decorators import check_user_exists
+from lnbits.helpers import template_renderer
+
+access_generic_router = APIRouter()
+
+
+def access_renderer():
+    return template_renderer(["access/templates"])
+
+
+@access_generic_router.get("/", response_class=HTMLResponse)
+async def index(request: Request, user: User = Depends(check_user_exists)):
+    return access_renderer().TemplateResponse(
+        "access/index.html", {"request": request, "user": user.json()}
+    )