Docs: Deprecate or remove IDUN dryode documentation

[catamgalvan]

Description

The IDUN dryode has been discontinued and is no longer supported or available for purchase. To keep the documentation accurate and prevent confusion for new users, its dedicated pages should either be removed or moved to "Deprecated" section.

Affected Pages / URL Paths

The product appears at least in the following sections of the documentation:

• Dedicated page: https://docs.openbci.com/ThirdParty/IDUN_Dryode/Dryode/
• Mentioned/Linked in: https://docs.openbci.com/GettingStarted/Biosensing-Setups/EEGSetup/

Note: A global search for "IDUN" or "dryode" should be performed to ensure no other references or sidebar links are left behind in other files.