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/theme.yaml

@@ -0,0 +1,10 @@
+slug: knel-contract
+name: 'KNEL Contract'
+type: theme
+version: 0.1.0
+description: 'KNEL services contract site. Inherits Quark2; adds the DocuSeal e-sign page template.'
+icon: file-text
+author:
+  name: Known Element Enterprises LLC
+keywords: contract
+license: AGPL-3.0