Add ntfy service configuration with Tailscale sidecar support

[jackspiering]

Pull Request Title: Add ntfy service configuration with Tailscale sidecar support

Description

Add ntfy service configuration with Tailscale sidecar support

Related Issues

• N/A

Type of Change

• Bug fix
• New feature
• Documentation update
• Refactoring

How Has This Been Tested?

Debian 13 trixie.

Docker version
Client: Docker Engine - Community
Version: 28.5.1
API version: 1.51
Go version: go1.24.8
Git commit: e180ab8
Built: Wed Oct 8 12:17:24 2025
OS/Arch: linux/amd64
Context: default

Server: Docker Engine - Community
Engine:
Version: 28.5.1
API version: 1.51 (minimum version 1.24)
Go version: go1.24.8
Git commit: f8215cc
Built: Wed Oct 8 12:17:24 2025
OS/Arch: linux/amd64
Experimental: false
containerd:
Version: v1.7.28
GitCommit: b98a3aace656320842a23f4a392a33f46af97866
runc:
Version: 1.3.0
GitCommit: v1.3.0-0-g4ca628d1
docker-init:
Version: 0.19.0
GitCommit: de40ad0

Checklist

• I have performed a self-review of my code
• I have added tests that prove my fix or feature works
• I have updated necessary documentation (e.g. frontpage README.md)
• Any dependent changes have been merged and published in downstream modules

Screenshots (if applicable)

Additional Notes

• N/A