[ENHANCE] Add blacklisting functionality

[lachlanglen]

Summary

See V2 contract interface. This is currently deployed to v2new.staging.nadabot.near and has been populated with data from production. Current contract admins are plugrel.near, lachlan.near, wendersonpires.near & carina.akaia.near. As an admin you should be able to make any necessary write actions in order to test the UI.

See V2 designs - see DEV NOTE comments for clarification & feel free to add additional comments in Figma, comment on this ticket or post in TG for any additional clarification!

Description

As an admin, I want to be able to blacklist (flag) accounts that have engaged in fraud or are bots. This feature allows an admin to blacklist accounts, providing a reason for doing so. (NB: the reason is not stored on chain, but rather emitted in an event). A blacklisted account will always return a human score of 0.

Acceptance Criteria

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Additional Information

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