Move seq_of_component_size into ComponentDataTrait

[noa-starkware]

Summary

• seq_of_component_size is now a default method on ComponentDataTrait in stark_verifier
• Removed the free functions and the now-empty component_utils modules in cairo_air and circuit_air
• All 17 call sites updated to method syntax: component_data.seq_of_component_size(...)

Stacks on #449. Part of audit cleanup (ilya/audit2 TODO comments).

🤖 Generated with Claude Code

[cursor]

PR Summary

Medium Risk
Touches core constraint-evaluation plumbing by adding a default method on ComponentDataTrait and updating many call sites; while intended as a pure refactor, any mismatch in seq_* column selection would affect constraint composition across components.

Overview
Moves seq_of_component_size from per-crate helper modules into stark_verifier as a default method on ComponentDataTrait, centralizing the logic that selects the correct seq_{log_size} preprocessed column based on the component’s instance-size bits.

Removes the now-redundant component_utils modules from cairo_air and circuit_air (and their prelude re-exports) and updates all call sites to use method syntax: component_data.seq_of_component_size(context, &acc.preprocessed_columns).

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[reviewable-StarkWare]

This change is 

[ilyalesokhin-starkware]

crates/stark_verifier/src/constraint_eval.rs line 84 at r1 (raw file):

        // Assert that the component size was one of the supported sizes
        use circuits::ops::eq;
        eq(context, sum_bits, context.one());

Suggestion:

        circuits::ops::eq(context, sum_bits, context.one());

[ilyalesokhin-starkware]

crates/stark_verifier/src/constraint_eval.rs line 76 at r1 (raw file):

            };

            let bit = self.get_n_instances_bit(context, log_size);

I think the motivation for moving this function was to avoid this abstraction.

Code quote:

let bit = self.get_n_instances_bit(context, log_size);