Don't they?. They have plenty of mobilization capability left on manpower alone and units from other military districts to deploy in the area. There is also the fact that they could increase the RuAF involvement in the whole affair. Then they could also make the ROE less restrictive and just blanket entire towns with artillery regardless of who is in there.
They can still hit targets in Lviv and other areas of Ukraine and they could also get Belarus involved from the North
So yes, they still have the hability to escalate.
Maybe, but considering their sabotages attempts within Ukraine in the occupied areas have already been of limited success, them being able to sabotage inside Russia are even already more limited.
The Kerch bridge could just have been pure luck, false flag or a number of other factors.
Couldn't or wouldn't?. Trying to answer that question with any certainty is just especulation on your part but so far, the way the Russians have been fighting, it seems to suggest more of a "wouldn't", for whatever reason.
Again, we don't know why. There is some sort of political game going on Russia where they taking their bureaucratic sweet ass time to react to stuff.
Have you guys forgotten the infamous blue screen speech, pretending to be in the streets of Kiev in February-Early March with just a t-shirt and no coat?. The guy isn't going to stay in Kiev to find out what might get hit in the city as an answer to jihading the Kerch Bridge.
Specially after he has been also called out in the west for begging for a pre-emptive nuclear strike on Russia.
