ddns-scripts: add EuroDNS provider

[heisenberg192]

Add EuroDNS provider for IPv4 and IPv6

Howto:

set [USERNAME] to username
set [PASSWORD] to password
set [DOMAIN] to domain

https://help.eurodns.com/s/article/How-do-I-configure-DYNDNS?language=en_US

📦 Package Details

Maintainer: @
_{(You can find this by checking the history of the package Makefile.)}

Description:

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🧪 Run Testing Details

OpenWrt 24.10.5 r29087-d9c5716d1d / LuCI openwrt-24.10 branch 25.340.26705~d88390b
OpenWrt One

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✅ Formalities

• I have reviewed the CONTRIBUTING.md file for detailed contributing guidelines.

If your PR contains a patch:

• It can be applied using git am
• It has been refreshed to avoid offsets, fuzzes, etc., using

  make package/<your-package>/refresh V=s

• It is structured in a way that it is potentially upstreamable
  _{(e.g., subject line, commit description, etc.)
  We must try to upstream patches to reduce maintenance burden.}