«أَنَا كَفَيْتُ مُهِمَّكَ»
It was I who took care of your important matter.
The overt anā (أنا) is placed before the verbal assertion and may mark the speaker as the special agent of the action. “Kafaytu muhimmaka” alone would identify the action and its first-person agent, but the separate prominent pronoun can contrast that agent with others: I did it, not someone else.
Not every preposed element proves absolute exclusivity. Preposing may signal focus, prominence, emphasis, or correction. A reading of restriction needs the support of the discourse context.