docs: typos and examples fixes (#11954)

* docs: typos and examples fixes

* fix notification example

www/apps/book/app/learn/fundamentals/data-models/write-migration/page.mdx

@@ -37,7 +37,7 @@ You can also write migrations manually. To do that, create a file in the `migrat
 
 For example:
 
-```ts title="src/modules/blog/migrations/Migration20240429.ts"
+```ts title="src/modules/blog/migrations/Migration202507021059.ts"
 import { Migration } from "@mikro-orm/migrations"
 
 export class Migration202507021059 extends Migration {