Add setting migration

src/migration.js

@@ -0,0 +1,27 @@
+import {settingsKey} from "./settings.js"
+
+const currentDataVersion = "1.3.0"
+
+export function performMigrations() {
+	if (!game.user.isGM)
+		return
+
+	let dataVersion = game.settings.get(settingsKey, "dataVersion")
+	if (dataVersion === "fresh install") {
+		// Migration from unnamed version. TODO Remove this in a future version
+		let speedAttribute = game.settings.storage.get("world").get(`${settingsKey}.speedAttribute`)
+		if (speedAttribute)
+			speedAttribute = speedAttribute.slice(1, speedAttribute.length - 1)
+		const speedAttributeDefault = game.settings.get(settingsKey, "speedProviders.native.setting.speedAttribute")
+		if (speedAttribute !== speedAttributeDefault)
+			game.settings.set(settingsKey, "speedProviders.native.setting.speedAttribute", speedAttribute)
+
+		let dashMultiplier = game.settings.storage.get("world").get(`${settingsKey}.dashMultiplier`)
+		const dashMultiplierDefault = game.settings.get(settingsKey, "speedProviders.native.setting.dashMultiplier")
+		if (dashMultiplier !== dashMultiplierDefault)
+			game.settings.set(settingsKey, "speedProviders.native.setting.dashMultiplier", dashMultiplier)
+		// End of unnamed version migration code
+		game.settings.set(settingsKey, "dataVersion", currentDataVersion)
+		return
+	}
+}