* core: implement eip-4399 random opcode

* core: make vmconfig threadsafe

* core: miner: pass vmConfig by value not reference

* all: enable 4399 by Rules

* core: remove diff (f)

* tests: set proper difficulty (f)

* smaller diff (f)

* eth/catalyst: nit

* core: make RANDOM a pointer which is only set post-merge

* cmd/evm/internal/t8ntool: fix t8n tracing of 4399

* tests: set difficulty

* cmd/evm/internal/t8ntool: check that baserules are london before applying the merge chainrules