Write about how to use Supabase with Wasp

[Martinsos]

Allegeldy it is important to run Supabase in transtaction mode, not in session mode?

Not quite sure, but we have this discord convo where user figured out some Supabase issues they had + another user said it was useful so, we should consider mkaing it part of the docs, or at least learning materials / guides: https://discord.com/channels/686873244791210014/1250831665995972729/1250831665995972729 .

[infomiho]

Maybe we should add it to learning materials to start and then when learning materials get promoted to a more prominent spot in the docs, it will be covered nicely.