v0.1: replace shell-rendered site with Grav-native pages + theme

- Drop site/ + RenderSite.sh: repo now carries grav/user/pages as
  native Grav markdown pages (home/services/terms/sign/execution)
- Add knel-contract theme: inherits quark2 via stream fallback, adds
  sign.html.twig (Twig) driving the DocuSeal flow through the APISIX
  gateway; esign wiring lives in the theme yaml for forks to retarget
- CreateDocument.sh refreshes the Grav services page from the
  rendered catalogs instead of invoking the removed site renderer

Ticket: https://projects.knownelement.com/issues/924

grav/user/themes/knel-contract/knel-contract.yaml

@@ -0,0 +1,17 @@
+enabled: true
+
+# Any quark2 template not overridden here falls through to quark2
+streams:
+  schemes:
+    theme:
+      type: ReadOnlyStream
+      prefixes:
+        '':
+          - user/themes/knel-contract
+          - user/themes/quark2
+
+# E-sign wiring (forks: point these at your own gateway/template)
+esign:
+  api_url: 'https://apigw.knownelement.com/contract-sign/api/submissions'
+  sign_url: 'https://esign.knownelement.com'
+  template_id: '2'