refactor: Break apart monolithic configuration schema (#1977)

[skip ci]

src/config/schema/elements/stock/state-label.ts

@@ -0,0 +1,11 @@
+import { z } from 'zod';
+import { elementsBaseSchema } from '../base';
+
+// https://www.home-assistant.io/lovelace/picture-elements/#state-label
+export const stateLabelSchema = elementsBaseSchema.extend({
+  type: z.literal('state-label'),
+  entity: z.string(),
+  attribute: z.string().optional(),
+  prefix: z.string().optional(),
+  suffix: z.string().optional(),
+});