docs: operate: customize: Tutorial for checkboxes in publish modal

Author: sakshamarora1

docs/operate/customize/extra_checkbox.md

@@ -0,0 +1,72 @@
+# Add extra checkboxes when publishing or submitting to community
+
+InvenioRDM allows you to customize the publish modal by adding extra checkboxes for user confirmation (e.g., terms of service, data policy). This is useful for compliance and custom workflows.
+
+## Define parameters to override
+
+You can override the default behavior of modals by customizing their parameters or injecting additional elements.
+
+### Define the extra checkbox fields (a list) using the extraCheckboxes parameter
+
+```javascript
+import { i18next } from "@translations/invenio_rdm_records/i18next";
+import { PublishModal } from "@js/invenio_rdm_records";
+import { parametrize } from "react-overridable";
+
+export const parameters = {
+  extraCheckboxes: [
+    {
+      fieldPath: "acceptTermsOfService",
+      text: i18next.t(
+        "I confirm that this record complies with the data policy and terms of service."
+      ),
+    },
+  ],
+};
+
+export const PublishModalComponent = parametrize(PublishModal, parameters);
+```
+
+![Publish modal with checkbox](imgs/extra_modal_checkboxes.png)
+
+### You can also inject extra UI elements before or after the checkboxes
+
+```javascript
+import { i18next } from "@translations/invenio_rdm_records/i18next";
+import { SubmitReviewModal } from "@js/invenio_rdm_records";
+import { parametrize } from "react-overridable";
+
+const LegalDisclaimer = () => (
+  <>
+    <p className="text-xs">
+      By publishing, you agree to our <a href="/terms" className="underline">terms of service</a>.
+    </p>
+    <p className="text-xs mt-1">This action is irreversible.</p>
+  </>
+);
+
+export const parameters = {
+  beforeContent: <p className="text-sm mb-2">Please review before continuing:</p>,
+  afterContent: <LegalDisclaimer />,
+};
+
+export const SubmitReviewModalComponent = parametrize(SubmitReviewModal, parameters);
+```
+
+![Submit Review modal with extra content](imgs/extra_modal_content.png)
+
+#### Override the components in the overridableRegistry mapping
+
+```javascript
+export const overriddenComponents = {
+  "InvenioRdmRecords.PublishModal.container": PublishModalComponent,
+  "InvenioRdmRecords.SubmitReviewModal.container": SubmitReviewModalComponent,
+};
+```
+
+And then re-build the assets for the changes to take effect.
+
+```sh
+invenio-cli assets build
+```
+

docs/operate/customize/imgs/extra_modal_checkboxes.png

@@ -135,6 +135,7 @@ nav:
               - Overview: "operate/customize/notifications.md"
               - Modify notifications: operate/customize/notifications_modify.md
           - Require a community to publish: "operate/customize/require_community.md"
+          - Add extra checkboxes when publishing: "operate/customize/extra_checkbox.md"
           - Restrict community creation: "operate/customize/restrict_community_creation.md"
           - Restrict access to pages: operate/customize/restrict_access.md
           - Search: