Chore update readme to use hetzner cloud init (#24)

* chore: update readme to use hetzner cloud init

* chore: update README.md with missing steps

* fix: tailscale placeholder

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: venkatamutyala

README.md

@@ -1,19 +1,53 @@
 # docker-compose-container-registry-pull-through-caches
 
+# Deployment
 
-# Requirements
+To deploy in hetzner, go to Hetzner cloud console and look for the project called "container-registry-cache".
+
+Create a new instance in hetzner cloud:
+- 3 or more vCPU's (e.g. CPX21 or CPX32)
+- Keep a public IPv4
+- Remove IPv6 address
+- Attach the firewall rule that blocks all incoming connections
+- Use cloud-init config below but update the --authKey for tailscale.
+
+
+You can create an authKey in tailscale as follows:
+
+<img width="745" height="1164" alt="image" src="https://github.com/user-attachments/assets/bfced0e9-e3e0-4f89-87ca-21b0497ad988" />
 
-Install the basics:
-```bash
-curl -fsSL https://get.docker.com -o get-docker.sh && sudo sh get-docker.sh && sudo apt-get update && sudo apt install tmux git -y && sudo apt-get clean
-```
 
+# cloud-init/config:
 
+```yaml
+#cloud-config
 
-# To deploy
+# --- 1. System Configuration ---
+# Sets the system hostname and manages the /etc/hosts file.
+# :exclamation:️ Replace "container-registry-cache-for-dev" with your desired hostname.
+hostname: container-registry-cache-for-dev
+manage_etc_hosts: true
 
-```bash
-git clone https://github.com/GlueOps/docker-compose-container-registry-pull-through-caches.git
-cd docker-compose-container-registry-pull-through-caches/
-docker compose up -d
+# --- 2. Setup Commands ---
+runcmd:
+  # Install Tailscale and Docker
+  - 'curl -fsSL https://tailscale.com/install.sh | sh'
+  - 'curl -fsSL https://get.docker.com -o get-docker.sh'
+  - 'sh get-docker.sh'
+  - 'sudo apt-get update && sudo apt install tmux git -y && sudo apt-get clean'
+
+  # Configure and connect to Tailscale in a single step
+  # :exclamation:️ Replace "tskey-auth-..." with your actual Tailscale auth key.
+  - ['tailscale', 'up', '--authkey=YOUR_TAILSCALE_AUTH_KEY_HERE', '--ssh']
+
+  # Secure the root account by disabling password login
+  - ['passwd', '-d', 'root']
+
+  # Deploy the Docker Compose application
+  # :exclamation:️ Replace the URL with the actual link to your compose file.
+  - 'cd /opt && git clone https://github.com/GlueOps/docker-compose-container-registry-pull-through-caches.git'
+  - 'cd /opt/docker-compose-container-registry-pull-through-caches && docker compose up -d'
 ```
+
+
+Once you have an instance running, update the `dev-only-registry` DNS entry to use the new tailscale IP of the node you just added and assuming everything is working destroy the old hetzner node and remove it from tailscale