AO3-7080 Prevent guest comments from suspended and banned accounts

[EchoEkhi]

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Issue

https://otwarchive.atlassian.net/browse/AO3-7080

Purpose

Prevent guest comments from suspended and banned accounts

Credit

EchoEkhi

[EchoEkhi]

Notes for the migration:
rake db:migrate
rake After:add_canonical_email

[Bilka2]

The migration in this PR needs to be updated to be have a timestamp after 12 November 2025, as defined in the schema file:

otwarchive/db/schema.rb

Line 13 in 1c45632

ActiveRecord::Schema[7.2].define(version: 2025_11_12_114418) do