docs: document gitea-first homelab deploys

Switch CLAUDE.md and AGENTS.md to Gitea-primary language. Remove
github-runner from the management plane now that Gitea Actions handles
Caddy reloads and famapp builds. Disable GitHub deploy workflow.
Update apply-compose.ps1 status text.

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

portainer-compose.yml

@@ -187,24 +187,6 @@ services:
     labels:
       - "com.centurylabs.watchtower.enable=false"
 
-  github-runner:
-    container_name: github_runner
-    image: myoung34/github-runner:latest
-    restart: unless-stopped
-    environment:
-      - ACCESS_TOKEN=${GITHUB_RUNNER_ACCESS_TOKEN}
-      - REPO_URL=https://github.com/ginnoir/homelabstack
-      - RUNNER_NAME=valhalla
-      - RUNNER_LABELS=self-hosted,Linux,x64
-      - RUNNER_SCOPE=repo
-      - DOCKER_GROUP_GID=1001
-    volumes:
-      - /var/run/docker.sock:/var/run/docker.sock
-      - /home/ginnoir/valhalla-lab:/valhalla-lab
-      - /config/caddy:/config/caddy
-    labels:
-      - "com.centurylabs.watchtower.enable=false"
-
   watchtower:
     container_name: watchtower
     image: containrrr/watchtower:latest