Content Rollback: Add notification message meta property

[leekelleher]

Description

The Content Rollback entity action kind (introduced in #21939) hard-coded its success notification to use the document-specific localization key rollback_documentRolledBack. This prevents other content types (e.g. Global Elements in v18) from supplying their own message.

Summary

• Adds an optional rollbackNotificationMessage meta property to the contentRollback entity action kind. Manifests can supply a localization key (or literal string) to use for the success notification.
• The Document rollback manifests (entity action and audit log action) opt in with #rollback_documentRolledBack, preserving the existing message.
• When a manifest does not set the property, the action falls back to a new generic #rollback_contentRolledBack ("Content has been rolled back") localization key.
• Replaces the unreachable "Notification context not found" throw with an optional-chained call.

Test plan

• Roll back a document — verify the existing "Document has been rolled back" notification still appears.
• Cancel the rollback modal — verify no notification is shown.

[Copilot]

Pull request overview

This PR updates the content rollback flow so the rollback modal returns entity metadata (unique, entityType) and the rollback entity action can show an entity-specific localized success notification (with a generic fallback), while also making the notification context access non-throwing.

Changes:

• Extend UmbContentRollbackModalValue to include unique/entityType (via UmbEntityModel) and submit those values from the modal.
• Update the rollback entity action to localize the success notification based on the returned entityType, and make notification context usage optional.
• Minor formatting cleanup in the entity-action manifest types.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
src/Umbraco.Web.UI.Client/src/packages/content/content/rollback/modal/types.ts	Makes the rollback modal’s return value include unique + entityType by extending UmbEntityModel.
src/Umbraco.Web.UI.Client/src/packages/content/content/rollback/modal/content-rollback-modal.element.ts	Submits { unique, entityType } on successful rollback instead of an empty object.
src/Umbraco.Web.UI.Client/src/packages/content/content/rollback/entity-action/types.ts	Formatting-only change to the rollback entity action manifest interface.
src/Umbraco.Web.UI.Client/src/packages/content/content/rollback/entity-action/content-rollback.action.ts	Uses returned entityType to build an entity-specific localization key and peeks a success notification via optional context.

[AndyButland]

Works as expected @leekelleher, and looks good. I've tested out the rollback from both the entity action and the audit log itself. Just a couple of inline comments to consider, then, unless you feel you need a more expert FE review, looks good to merge.