I think we are pretty safe.
Only lunatic here is Dodik but I doubt Putin cares about him, and I really don't see any point of Putin invading Bosnia.
There are 500 NATO soldiers here, 700 regular EUFOR soldiers plus 500 new as of yesterday just in case. That's not too much but it's still different to Ukraine. EU is slow on our situation but they were pretty clear these past few days that despite us not being NATO member, it's quite obvious they've invested here a lot and they are ready to defend us. Our troops are part of NATO for years, one of my best mates is currently in Central Africa with NATO for 6 months, all paid by Americans and NATO.
Of course if Putin tries to go for other countries then we are fecked as anyone and it's basically WWIII.
And regarding Serbia, I'd say we are not in danger from them, Putin isn't getting Vucic's support who is heading for EU so obviously Putin won't care too much about them either, so Vucic won't feel very brave to go against country that is supported by EU either.