feat: RLS guard on table

[onx2]

Description of Changes

Draft to add a proc macro that wraps the current client visibility filter so RLS can be applied with less boilerplate and directly on the table structs.

https://discord.com/channels/1037340874172014652/1423724267203334298

Some other things that should be considered:

• Since the intent is to attach to a struct with the table macro, maybe this should enforce that the table macro exists?
• IDK if possible but maybe even verify the SQL relates to that table name? If it isn't possible maybe we can extend the table macro to accept guards so we can read the metadata?
• Edge cases 🤷🏼
• Tests? I didn't see any for the client visibility filter though

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