no this is not worship and everything that you have mentioned has been done during the Prophet’s, Sallallahu alaihi wa alehi wa sallam, life or by his companions.
his wudu water did not hit the ground. i’ll stop there on this
the decorations are in the Quran and Sunnah, spending money on this occasion is mustahab
you have no idea of the reverence of the Prophet required to be Believers.