Feat/metal/ff reduce

[moven0831]

includes significant changes to the bigint and field modules in the mopro-msm project and the introduction of new result structures to handle carry values, updates to arithmetic functions to use these structures, and the addition of new tests for field reduction.

Changes to BigInt arithmetic functions:

• mopro-msm/src/msm/metal_msm/shader/bigint/bigint.metal: Updated bigint_add_unsafe, bigint_add_wide, bigint_sub, and bigint_sub_wide functions to use new BigIntResult and BigIntResultWide structures to handle carry values.

Changes to field arithmetic functions:

• mopro-msm/src/msm/metal_msm/shader/field/ff.metal: Added a new ff_reduce function and updated ff_add and ff_sub functions to use the new BigIntResult structure.

Updates to kernel functions:

• mopro-msm/src/msm/metal_msm/shader/bigint/bigint_add_unsafe.metal: Modified kernel function to use new BigIntResult structure.
• mopro-msm/src/msm/metal_msm/shader/field/ff_add.metal: Updated kernel function to use new ff_add function.

Addition of new tests:

• mopro-msm/src/msm/metal_msm/tests/field/ff_reduce.rs: Added new tests for the ff_reduce function to ensure correct behavior when a is less than p and when a is between p and 2p.
• mopro-msm/src/msm/metal_msm/tests/field/mod.rs: Included the new ff_reduce test module.

Structural changes:

• mopro-msm/src/msm/metal_msm/shader/misc/types.metal: Added new BigIntResult and BigIntResultWide structures to handle carry values in arithmetic operations.