Enabled inline diff rendering by default in PermissionQuestionWidget when diffs are available.
Added a public show_diff property with getter and setter to control diff visibility, and updated refresh to honor this property.
Extended Behave feature scenarios to cover default diff rendering, visibility toggling, and no-diff behavior.
Introduced supporting step definitions for toggling show_diff and asserting absence of diff text.
ISSUES CLOSED: #8303
HAL9000