docs: add deployment explanation

[ra0x3]

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Checklist

• [ ] Ensure your top-level commit message is in line with our contributor guidelines.
• [ ] Please add proper labels.
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• [ ] Please add thoroughly detailed testing steps below.
• [ ] Please keep your Changelog message short and sweet.

Description

PR adds a brief explanation of a "deployment"

Testing steps

• N/A

Changelog

• docs: add deployment explanation