Fix visibility guards in bundled groups

[shukudaidayo]

Summary

• Preserve array positions when array-expanded fields are hidden by visibility rules
• Allow calldata visibility checks to match descriptor-friendly uint/address literals
• Add regression tests for hidden guard fields in bundled calldata and EIP-712 groups

Context

This was surfaced while testing the Ocarina ERC-7730 registry submission: ethereum/clear-signing-erc7730-registry#2598.

The runner reported failures for descriptors that use hidden visible.mustBe guard fields inside bundled offer/receive/tip item groups:

• calldata uint guard values decoded as ABI hex words did not match descriptor literals like "1" or "2"
• bundled groups skipped hidden array-expanded fields instead of preserving their array positions, causing sibling array fields to fail the equal-length check

Details

For bundled groups, array-expanded fields now preallocate one bundle slot per source array item and leave the slot empty when a field is hidden. This keeps sibling array fields aligned even when a guard field such as itemType is intentionally hidden with visible.mustBe.

For calldata visibility, comparisons now keep exact JSON matching but also support common descriptor literals:

• decimal string or numeric literals for ABI uint values, e.g. "1" or 1
• case-insensitive 0x... string comparison for addresses / hex values

Validation

• cargo test --quiet
• Ocarina calldata testsv2: 3/3 passed
• Ocarina EIP-712 testsv2: 3/3 passed