docs: add ldn, update add-on versions

[davlgd]

This PR adds ldn region in documentation, update some versions.

I've moved the region part at the beginning of the document to reduce repetitions and maintenance. Let me know if you want to do that differently

[Copilot]

Pull Request Overview

This PR updates the documentation by adding the new “ldn” region and consolidating the supported region information to reduce duplication, as well as updating addon versions.

• Introduced a consolidated “Supported region” section at the beginning of the document.
• Added “London (ldn)” to the supported region table.
• Updated and removed duplicate version and region tables to improve maintainability.

[FlorentinDUBOIS]

Hello,

Thank you for your pull request, but we need to update the code source to match the documentation that you propose.
This process use the clevercloud-sdk-rust and all versions and regions are retrieved from there.
Besides, we cannot mutualized region as there are not the same across product for example, pulsar is only available through paris