architects new ban system, monkey saws in proper system bans for client security (#7324)

code/modules/client/data/player_ban.dm

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+//* This file is explicitly licensed under the MIT license. *//
+//* Copyright (c) 2025 Citadel Station Developers           *//
+
+/datum/player_ban
+	var/ban_id
+	var/match_player_id
+	var/match_ckey
+	var/match_ip
+	var/match_computer_id
+	var/type_class
+	var/type_id
+	/// plaintext generated by subsystem
+	/// * not always filled out; if looking up metadata
+	var/list/edit_log

code/modules/client/data/player_ban_cache.dm

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+//* This file is explicitly licensed under the MIT license. *//
+//* Copyright (c) 2025 Citadel Station Developers           *//
+
+/**
+ * Contains all active bans for a player for quick lookup.
+ * * Will only contain one ban per relevant thing; e.g. if someone's somehow triple-jobbanned
+ *   from captain, it'll only have one.
+ */
+/datum/player_ban_cache
+	var/total_bans
+	var/datum/player_ban/is_server_banned
+	/// id = entry
+	var/alist/datum/player_ban/currently_banned_role_ids
+	/// class = entry
+	var/alist/datum/player_ban/currently_banned_role_classes