Retire shorashim.ch; Gitea brand becomes Bikoret

- service.yaml: the shorashim.ch host rule is gone from the Ingress;
  the no-host catch-all stays for http://185.19.28.170
- gitea-public-patch.yaml: APP_NAME "Shorashim" → "Bikoret" (title and
  brand on every Gitea page)
- shorashim-ch-takedown.sh: the operator's apply (ingress, orphan
  mcp.shorashim.ch TLS secret, Gitea patch + rollout) with verification
- KOHEN.md, AGENTS.md: examples and the endpoint table use bikoret.ch

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

deploy/k8s/gitea-public-patch.yaml

@@ -26,3 +26,7 @@ spec:
               value: "git.bikoret.ch"
             - name: GITEA__server__SSH_DOMAIN
               value: "git.bikoret.ch"
+            # [DEFAULT] APP_NAME — the title and brand on every Gitea page.
+            # Was "Shorashim"; the system is named Bikoret (PRD §0).
+            - name: GITEA____APP_NAME
+              value: "Bikoret"