Witgen: Pass range constraints to callee

[georgwiese]

Cherry-picked b1a07bd from #1380, and extended on it.

Fixes #1382.

With this PR, a lookup like selector { byte_lower + 256 * byte_upper } in { <some other machine> } works, even if the range constraints on byte_lower and byte_upper are not "global". For example, they could be implemented as selector { byte_lower } in { BYTES } (i.e., byte_lower is only range constrained when the machine call is active).

To make this work, I changed the Machine::process_plookup interface like this:

    fn process_plookup<'b, Q: QueryCallback<T>>(
        &mut self,
        mutable_state: &'b mut MutableState<'a, 'b, T, Q>,
        identity_id: u64,
-       args: &[AffineExpression<&'a AlgebraicReference, T>],
+       caller_rows: &'b RowPair<'b, 'a, T>,
    ) -> EvalResult<'a, T>;

The RowPair passed by the caller contains all range constraints known at runtime. The LHS of the lookup (or permutation) is no longer evaluated by the caller but by the callee. For this, the callee needs to remember the identity associated with the identity_id (before this PR, most machines just remembered the RHS, not the full identity). I don't expect there to be any performance implications, because we only invoke one machine (since #1154).

Benchmark results

executor-benchmark/keccak
                        time:   [14.609 s 14.645 s 14.678 s]
                        change: [-2.5984% -2.3127% -2.0090%] (p = 0.00 < 0.05)
                        Performance has improved.

executor-benchmark/many_chunks_chunk_0
                        time:   [39.299 s 39.380 s 39.452 s]
                        change: [-3.9505% -3.6909% -3.4063%] (p = 0.00 < 0.05)
                        Performance has improved.

[georgwiese]

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[leonardoalt]

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