Rizvan
The specific proper-name form 'Rizvan' does not appear as a proper name in the Quran; the root (r-ḍ-w) is part of Islamic vocabulary. 'Ridwan' appears in later Islamic tradition as the name of an angel.
They are regional/phonetic variants of the same Arabic root rijwan/riḍwān. 'Ridwan' is closer to Arabic pronunciation; 'Rizwan' and 'Rizvan' reflect Persian/Turkic/Balkan adaptations.
Yes. It carries a positive Islamic meaning (God's approval, paradise) and is used historically among Muslim communities.
Historically the variant Rizvan has been found in Bosnian, Balkan, and some Turkic onomastic records as a localized form of the Arabic name Ridwan/Rizwan.
Pronounced RIZ-van in Bosnian/Turkic usage, with stress on the first syllable.