Condense Database Migrations (#17103)

* Condense Database Migrations

Condenses the Database Migrations into a new initial schema.
Also adds some instructions to the Database Readme for existing setups.

* Update readme/delete changed migrations since pr creation

* Reworks a bit how the previous migrations are handled and updates the instructions accordingly

* Expand the readme with baseline/migrate

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Co-authored-by: Werner <Arrow768@users.noreply.github.com>

SQL/migrate-2017/V029__player_notifications.sql

@@ -0,0 +1,16 @@
+--
+-- Notifications for Players
+--
+CREATE TABLE `ss13_player_notifications` (
+	`id` INT(10) UNSIGNED NOT NULL AUTO_INCREMENT,
+	`ckey` VARCHAR(50) NOT NULL COLLATE 'utf8_bin',
+	`type` ENUM('player_greeting','player_greeting_chat','admin','ccia') NOT NULL COLLATE 'utf8_bin',
+	`message` VARCHAR(50) NOT NULL COLLATE 'utf8_bin',
+	`created_by` VARCHAR(50) NOT NULL COLLATE 'utf8_bin',
+	`created_at` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+	`acked_by` VARCHAR(50) NULL DEFAULT NULL COLLATE 'utf8_bin',
+	`acked_at` DATETIME NULL DEFAULT NULL,
+	PRIMARY KEY (`id`)
+)
+COLLATE='utf8_bin'
+ENGINE=InnoDB;