fix: pin gitea to 1.26.1 and disable Watchtower to prevent broken image pulls

Watchtower pulled gitea/gitea:latest three times (Mar 12, Apr 19, Apr 25)
and at least one pull resulted in a broken image with git binary failures.
Pin to stable gitea/gitea:1.26.1 and add watchtower.enable=false label
so the image is only updated by deliberate human action.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

compose/hf-pdocker-02/gitea/docker-compose.yml

@@ -1,8 +1,10 @@
 services:
   gitea:
-    image: gitea/gitea:latest
+    image: gitea/gitea:1.26.1
     container_name: gitea
     restart: unless-stopped
+    labels:
+      - "com.centurylinklabs.watchtower.enable=false"
     ports:
       - "3003:3000"
       - "2222:22"