Unify the OuterCircuit in DPC

[weikengchen]

Motivation

This PR would go to #300. The PR unifies the OuterCircuit in DPC.

Test Plan

Will wait for the CI for the results. Keys for the outer circuit need to be resampled.

Related PRs

This is part of #300.

[weikengchen]

Parameters need to be resampled.

A local resampling and integration tests have been done.

• testnet1 cannot succeed because NoopProgramCircuit always point to testnet2's parameters, which requires a separate fix in Unify DPC programs #300. One needs to decide where to put the NoopProgram parameters (in DPC parameters? though NoopProgram is for test purposes).
• testnet2 passes.

It is ready for review and merge.

[ljedrz]

Left a few small suggestions.

[weikengchen]

Left a few small suggestions.

Thanks. The issues have been resolved.

[weikengchen]

The recent update in this PR solves a few remaining issues in #300:

• allow testnet1 and testnet2 to load different parameters for Program SNARK, using the NETWORK_ID
• SRS has been refactored so that it does not cause an overhead of to_bytes_le
• Name change for URS in Marlin.

It is ready to be merged into #300 and then updated with a parameter resampling.

[howardwu]

LGTM. Worth calling out that this PR also introduces ToBits functionality for structs that implement the Field trait, thank you @weikengchen!

For the 3 failing CI, 2 are due to resampling parameter requirements, and 1 is a clippy failure from PR 300, these will get resolved in PR #300.