revert: remove Docker Hub integration from release workflow and README

Restores release workflow to ghcr.io-only publishing.
Removes Docker Pulls badge from README.

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

.github/workflows/release.yml

@@ -26,12 +26,6 @@ jobs:
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
 
-      - name: Log in to Docker Hub
-        uses: docker/login-action@v3
-        with:
-          username: ${{ secrets.DOCKERHUB_USERNAME }}
-          password: ${{ secrets.DOCKERHUB_TOKEN }}
-
       - name: Extract version from tag
         id: version
         run: echo "VERSION=${GITHUB_REF#refs/tags/}" >> $GITHUB_OUTPUT
@@ -48,8 +42,6 @@ jobs:
           tags: |
             ${{ env.REGISTRY }}/shankar0123/certctl-server:${{ steps.version.outputs.VERSION }}
             ${{ env.REGISTRY }}/shankar0123/certctl-server:latest
-            ${{ secrets.DOCKERHUB_USERNAME }}/certctl-server:${{ steps.version.outputs.VERSION }}
-            ${{ secrets.DOCKERHUB_USERNAME }}/certctl-server:latest
           cache-from: type=gha
           cache-to: type=gha,mode=max
 
@@ -62,8 +54,6 @@ jobs:
           tags: |
             ${{ env.REGISTRY }}/shankar0123/certctl-agent:${{ steps.version.outputs.VERSION }}
             ${{ env.REGISTRY }}/shankar0123/certctl-agent:latest
-            ${{ secrets.DOCKERHUB_USERNAME }}/certctl-agent:${{ steps.version.outputs.VERSION }}
-            ${{ secrets.DOCKERHUB_USERNAME }}/certctl-agent:latest
           cache-from: type=gha
           cache-to: type=gha,mode=max
 

README.md

@@ -25,7 +25,6 @@ certctl is a self-hosted platform that automates the entire certificate lifecycl
 [![License](https://img.shields.io/badge/license-BSL%201.1-blue.svg)](LICENSE)
 [![Go Report Card](https://goreportcard.com/badge/github.com/shankar0123/certctl)](https://goreportcard.com/report/github.com/shankar0123/certctl)
 [![GitHub Release](https://img.shields.io/github/v/release/shankar0123/certctl)](https://github.com/shankar0123/certctl/releases)
-[![Docker Pulls](https://img.shields.io/docker/pulls/shankar0123/certctl-server)](https://hub.docker.com/r/shankar0123/certctl-server)
 
 ## Documentation