fix: use number of storage slots from native account in delta commitment

[PhilippGackstatter]

This PR contains a couple of batched fixes from the audit reports, addressing:

• L-02 Misleading Documentation (Report 1)
• L-03 Transaction Script Program Does Not Load the Corresponding Arguments (Report 2)
• L-04 Delta Commitment Computation May Use Foreign Account Context (Report 2)
• L-06 Misleading Documentation (Report 2)
• L-07 Incomplete Procedure Documentation (Report 2)

Summary

• Introduce memory::get_native_num_storage_slots for use in account_delta::compute_commitment to make sure the delta commitment is always computed against native account state.
• Fix misleading documentation, incorrect stack comments, and incomplete procedure documentation across the MASM transaction kernel, as identified by the transaction kernel audits
• Remove unused MAX_NUM_FOREIGN_ACCOUNTS Rust constant that incorrectly stated 64 foreign accounts (the actual limit is 63 foreign + 1 native = 64 total, enforced by MASM's MAX_FOREIGN_ACCOUNT_PTR)