Not really. If you say "all" didn't understand it the same way, well there is a possibility that a few disagreed or what ever. These are all vague statements.
Sunni's and Shia's both in their respective mainstream theological documents understood and still understand this phrase the same way. This is the official view of Islam.
Brother. It seems like you dont understand what you mean by "Shia and Sunni ahadith".
Anyway, never mind that. Since you are talking about a sectarian issue you are looking for extra quranic, traditional, hadith based information. So here's a few for you to ponder.
1. This is What Yusuf Ali says in his translation. And before you ask I should tell you that He is not a Sunni, he is Shi, Bohri. Attached image. I am too lazy to type it.
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2. Let me politely clear a misunderstanding you have. You speak of Shia and Sunni ahadith as if Shi's dont trust Sunni hadith because its sunni. Wrong. They trust certain narrators, like the prophets companions. They dont trust certain narrators. And they dont believe in naming these books Sahih because these people fallible humans so you cant put a blanket name like Sahih. But they trust the hadith. Do you understand? Be very clear about that. I know that throughout your conversation you seem to have this miscommunication.
Anyway. You wanted a hadith.
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That one says specifically that the line of prophets is closed with Muhammed.
And brother, there are many other ahadith that speaks of end times, and that there will be a number of impostors calling themselves prophets, etc etc. All in all, the theme of these narrations is that Muhammed is the last prophet and all of it stems from this particular verse in the OP. All this tradition talk is because its you who require it. I am not stating a view. I am only giving the information you are asking.
We know what the author of the Quran meant because its just language. You need to understand the classical language in order to understand what the author meant (whoever you think wrote it). The most classical understanding of the language is that it means Muhammed is the last Nabi.
Peace.