Add the mock circuit verifier's input hint

[YairVaknin-starkware]

Implements MOCK_CIRCUIT_VERIFIER_LOAD_INPUT for the mock circuit verifier program (starkware/cairo/cairo_verifier/mock_circuit_verifier.cairo, added on the main-repo side): loads the MockCircuitVerifierInput program input and sets ids.preprocessed_root / ids.output_values (eight u32 words each, in fresh segments) and ids.n_steps. The mock stands in for the real stwo circuit verifier in the circuit-unpacking applicative bootloader's flow tests: it computes the same output digest D from the given root and output values.

Stack (2/3): aggregator scope var (#393) ← this ← circuit applicative BL hints.

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This change is 

[cursor]

PR Summary

Low Risk
Isolated test/mock hint path with no auth or production verifier changes; covered by unit tests.

Overview
Adds Rust support for MOCK_CIRCUIT_VERIFIER_LOAD_INPUT, used by the mock circuit verifier Cairo program in circuit-unpacking applicative bootloader flow tests (stand-in for the real stwo circuit verifier).

A new MockCircuitVerifierInput type (n_steps, preprocessed_root, output_values as u32 vectors) is deserialized from program JSON. The hint loads each root/values list into fresh VM segments (as felts) and sets ids.preprocessed_root, ids.output_values, and ids.n_steps. The hint is registered on MinimalBootloaderHintProcessor alongside other applicative bootloader hints, with unit tests for happy path and missing-id failures.

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[codecov]

Codecov Report

❌ Patch coverage is 99.15966% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 68.42%. Comparing base (efc698e) to head (4fb6a87).

Files with missing lines	Patch %	Lines
...ro-program-runner-lib/src/hints/hint_processors.rs	50.00%	1 Missing ⚠️

Additional details and impacted files

@@                             Coverage Diff                             @@
##           yairv/aggregator_program_hash_scope_var     #394      +/-   ##
===========================================================================
+ Coverage                                    67.80%   68.42%   +0.62%     
===========================================================================
  Files                                           41       42       +1     
  Lines                                         5892     6011     +119     
===========================================================================
+ Hits                                          3995     4113     +118     
- Misses                                        1897     1898       +1     

Files with missing lines	Coverage Δ
.../src/hints/circuit_applicative_bootloader_hints.rs	100.00% <100.00%> (ø)
crates/cairo-program-runner-lib/src/hints/types.rs	71.06% <ø> (ø)
...ro-program-runner-lib/src/hints/hint_processors.rs	63.25% <50.00%> (-0.10%)	⬇️

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[OmriEshhar1]

@OmriEshhar1 reviewed 5 files and all commit messages, and made 1 comment.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on Gali-StarkWare and YairVaknin-starkware).

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crates/cairo-program-runner-lib/src/hints/circuit_applicative_bootloader_hints.rs at r1 (raw file):
consider naming the file mock_circuit_verifier_hints.rs (instead of circuit_applicative_bootloader_hints.rs)

[OmriEshhar1]

@OmriEshhar1 made 1 comment and resolved 1 discussion.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on Gali-StarkWare).

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crates/cairo-program-runner-lib/src/hints/circuit_applicative_bootloader_hints.rs at r1 (raw file):

Previously, OmriEshhar1 wrote…

consider naming the file mock_circuit_verifier_hints.rs (instead of circuit_applicative_bootloader_hints.rs)

OK. I see in PR 395 that you decided to put the hints of circuit_applicative_bootloader and the hints of mock_circuit_verifier in the same place.
I'll leave it to you to decide if you want to keep it in 1 file, or separate to 2 files.
(changed to non-blocking)

[OmriEshhar1]

Reviewable status: all files reviewed, 1 unresolved discussion (waiting on Gali-StarkWare and YairVaknin-starkware).

[YairVaknin-starkware]

@YairVaknin-starkware made 1 comment and resolved 1 discussion.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on Gali-StarkWare).

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crates/cairo-program-runner-lib/src/hints/circuit_applicative_bootloader_hints.rs at r1 (raw file):

Previously, OmriEshhar1 wrote…

OK. I see in PR 395 that you decided to put the hints of circuit_applicative_bootloader and the hints of mock_circuit_verifier in the same place.
I'll leave it to you to decide if you want to keep it in 1 file, or separate to 2 files.
(changed to non-blocking)

I prefer it that way since it's only one hint that will only be used in the context of the circuit applicative bl anyway.

[Gali-StarkWare]

just move the tests to a different file

@Gali-StarkWare reviewed 5 files and all commit messages, and made 1 comment.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on YairVaknin-starkware).