docs: add Proofreading checkboxes to i18n plugin docs

Author: ivictbor

adminforth/documentation/docs/tutorial/05-Plugins/10-i18n.md

@@ -325,6 +325,63 @@ If you want to limit access to translations resource only to developers or trans
 
 Please note that access to "Translate selected" bulk action which uses LLM AI translation adapter is determined by allowedActions.edit permission of resource.
 
+## Proofreading checkboxes
+
+You can enable didicated checkboxes for proofreading translations. This will allow proofreaders to check each translation and mark it "reviewed" or "not reviewed".
+
+TO enable this options add TEXT column to the resource.
+
+If using prisma, add something like this:
+
+```ts title='./schema.prisma'
+model translations {
+  ...
+    completedLangs   String?
+  //diff-add
+    reviewed          String? 
+    
+    // we need both indexes on en_string+category and separately on category
+    @@index([en_string, category])
+    @@index([category])
+    @@index([completedLangs])
+}  
+```
+
+And add column to the resource:
+
+```ts title='./resources/translations.ts'
+{
+  ...
+  columns: [
+    ...
+    {
+      name: "reviewed",
+      type: AdminForthDataTypes.JSON, // should be JSON type
+      label: 'Reviewed',
+      showIn: {
+        all: false
+      },
+    },
+  ],
+}
+```
+
+
+Now just add `reviewedCheckboxesFieldName` to the plugin options:
+
+```ts title='./resources/translations.ts'
+  plugins: [
+    new I18nPlugin({
+      ...
+      reviewedCheckboxesFieldName: 'reviewed',
+    }),
+  ],
+```
+This will add checkboxes to the translations resource:
+
+![alt text](image-5.png)
+
+
 ## Translations in custom APIs
 
 Sometimes you need to return a translated error or success message from your API. You can use special `tr` function for this.