fix: move CRDs to Helm crds/ directory for proper ordering

v0.15.6:
- CRDs moved from subchart templates/ to parent crds/ directory
  Helm applies crds/ BEFORE any templates → no race condition
- crds subchart disabled (crds.enabled: false)
- Removed template tags from CRD YAML (crds/ is plain YAML)
- Webhook failurePolicy: Ignore (from v0.15.5)
- IPAddressPool/L2Advertisement as normal templates (no hooks)

Author: Peker Oksuz

charts/metallb/Chart.yaml

@@ -18,4 +18,4 @@ name: metallb
 sources:
 - https://github.com/metallb/metallb
 type: application
-version: 0.15.5
+version: 0.15.6