fix panic when guest accesses higher regions of memory

[SchmErik]

fix panic when guest accesses higher regions of memory

[SchmErik]

This is slightly easier than I thought mainly because I was conflating 2 things into 1. Here's what I ran into:

1. zkVM panicking on out of bounds array access in the resident field of monitor
2. zkVM guest accessing unallowed regions of memory

Internally, the zkVM is allowed to access parts of memory that the guest cannot (the region starting at 0x0C00_0000 has a lot of important system state that the guest has no business tampering with for its own good). However, we need to enable the guest to understand which memory regions should not be accessed. In our effort to prevent panics we should definitely do 1 and I have a draft of this (which entails putting Result<()> as a function signature in a bunch of functions) but 2 only requires modifying the parts that rrs touches which is this impl