refactor(config)!: Move scheduler out of device_manager

Due to changes made in mlua the new scheduler is much simpler. It also
had no real business being part of the device manager, so it has now been
moved to be part of the returned config.

config.lua

@@ -57,7 +57,7 @@ local function check_battery(device, battery)
 		low_battery[id] = nil
 	end
 end
-device_manager:schedule("0 0 21 */1 * *", function()
+local function notify_low_battery()
 	-- Don't send notifications if there are now devices with low battery
 	if next(low_battery) == nil then
 		print("No devices with low battery")
@@ -76,7 +76,7 @@ device_manager:schedule("0 0 21 */1 * *", function()
 		tags = { "battery" },
 		priority = "default",
 	})
-end)
+end
 
 --- @class OnPresence
 --- @field [integer] fun(presence: boolean)
@@ -742,17 +742,19 @@ devs:add(devices.ContactSensor.new({
 	battery_callback = check_battery,
 }))
 
-device_manager:schedule("0 0 19 * * *", function()
-	bedroom_air_filter:set_on(true)
-end)
-device_manager:schedule("0 0 20 * * *", function()
-	bedroom_air_filter:set_on(false)
-end)
-
 ---@type Config
 return {
 	fulfillment = {
 		openid_url = "https://login.huizinga.dev/api/oidc",
 	},
 	devices = devs,
+	schedule = {
+		["0 0 19 * * *"] = function()
+			bedroom_air_filter:set_on(true)
+		end,
+		["0 0 20 * * *"] = function()
+			bedroom_air_filter:set_on(false)
+		end,
+		["0 0 21 */1 * *"] = notify_low_battery,
+	},
 }