Private Input circuit

[naure]

Implement the supporting circuit for private input.

This will enable https://github.com/scroll-tech/ceno/discussions/607

Plan:

• Solution based on memory initialization (as opposed to solutions based on LOAD / STORE circuits).
• Constrain the content to the u32 range.
• Assume a contiguous range of addresses so we can use the SetTableSpec::DynamicAddr optimization.
• Attempt to make the range and range size dynamic.

[hero78119]

Related to marked of TODOs here https://github.com/scroll-tech/ceno/blob/6ea3beeceb2b82a51af6d0dfd0bd8e0ef70aabd1/ceno_zkvm/src/tables/ram/ram_impl.rs#L402-L417

In the end it seems to support {Dyn, Fix} x {Volatile, Non Volatile}, in totally 4 combination