"And, why are you worried for pen & paper incident, after that day, Prophet(PBUH) had enough time to declare succession or that sort of thing, but no sign or trace of IMAMAH there"
I'm not worried the slightest. And we aren't talking about Imamah. So I don't know why you keep bringing it in. Only to divert attention that is. Umar wasn't interested in what the Prophet s.a.w had to write by saying "you have the book of Allah with you, that is sufficient for us". Companions raised their voices in front of the Prophet s.a.w and argued in front of him. Some said he should be given the own and paper and should be allowed to write. The others disagreed. The behaviour was absolutely disgusting and in front of the Prophet s.a.w You can try hard as you want. It is what it is. And you can't wash it away or brush it under the carpet. I know how desperate you are.
"Allah taught sahaba how to behave among themselves while in front of Prophet(PBUH)"
And how exactly did they behave in front of the Prophet s.a.w is crystal clear when he asked for pen and paper. Stop protecting the guilty by dragging this on.
"Allah has mentioned them as those who have already believed"
I'm not questioning their belief, I'm just pointing out their behaviour and stance.
"which declared forgiveness for those who have acted upon the command of the 2nd ayat"
I'm not questioning whether or why they were forgiven or let off. Just pointing out that certain actions and behaviour puts you below others. You can't say, do, act and behave the way you want and then are placed above the others or given superiority above others. It's not just or fair. And it's beyond reason.
I provided a hadith as a proof that, Umar(ra) attained success in the test of Allah, and achieved forgiveness and great reward- which was mentioned in the ayat later. However, you are saying that you don't care whatever Allah declared , you want to write your own philosophy.
The behavior of the sahaba was due to the physical condition of prophet(sallallahu alaihi wasallam), they were too much worried for him and and confused about whether to arrange writing in that terrible pain or not- this was the only tension. You can't claim that they were making chaos deliberately to snatch Imamah from Ahlul Bayt!
WHatever Umar said , was to not trouble Prophet( صلى الله عليه وسلم) when he was suffering from pained, he said-
فَقَالَ بَعْضُهُمْ إِنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَدْ غَلَبَهُ الْوَجَعُ وَعِنْدَكُمُ الْقُرْآنُ، حَسْبُنَا كِتَابُ اللَّهِ
'Allah's Messenger (ﷺ) is seriously ill and you have the (Holy) Qur'an. Allah's Book is sufficient for us.'
Believing the perfection of Quran and trying to relief Prophet( صلى الله عليه وسلم) from the troubles was wrong according to you?
for your kind information, Ummah got the message which was to be conveyed by Prophet( صلى الله عليه وسلم) -
" .....Leave me. I am better in the state (than the one in which you are engaged). I make a will about three things: Turn out the polytheists from the territory of Arabia; show hospitality to the (foreign) delegations as I used to show them hospitality. He (the narrator) said: He (Ibn Abbas) kept silent on the third point, or he (the narrator) said: But I forgot that."
https://sunnah.com/muslim/25/29I am bringing Imamah here, because, that's the missing brick in the puzzle of Shiasm. We sunnis do not think that Islam lost any important things by these types of incidents or prophethood was failed to convey any important rulings just because of the so called "chaos" of sahaba.