feat: add account deletion functionality with cascade delete for work… (#33)

* feat: add account deletion functionality with cascade delete for workspace relations

* fix: add cascade delete to workspace user foreign key constraints

* fix: change onDelete action to set null for user references in schema

* feat: tweak design

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Co-authored-by: Henry <henry_ball@hotmail.co.uk>
Co-authored-by: Henry <30578846+hjball@users.noreply.github.com>

packages/db/migrations/20250605101155_AddCascadeDeleteToCardRelations.sql

@@ -76,4 +76,4 @@ DO $$ BEGIN
  ALTER TABLE "card_comments" ADD CONSTRAINT "card_comments_deletedBy_user_id_fk" FOREIGN KEY ("deletedBy") REFERENCES "public"."user"("id") ON DELETE cascade ON UPDATE no action;
 EXCEPTION
  WHEN duplicate_object THEN null;
-END $$;
+END $$;