feat(behandel): behandel-portal app — medewerker login + werkbak with decide (refs #13)

Scaffold apps/behandel (mirrors self-service): medewerker-realm OIDC login, the werkbak page

listing registrations awaiting beoordeling (GET /behandel/werkbak) with goedkeuren/afwijzen

actions (POST /behandel/registrations/{id}/decide) that refresh the list, plus Dockerfile and

same-origin nginx reverse proxy for /behandel/ (ADR-0013; S-12).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

apps/behandel/public/config.json

@@ -0,0 +1,3 @@
+{
+  "authority": "http://localhost:8180/realms/medewerker"
+}