CIP-0068 | Support multi-asset metadata a la CIP-0025

[thaddeusdiamond]

Add version 4 metadata support with 721-ERC-style mappings to NFT (222), FT (333) and RFT (444) standards, ensuring consistency across all asset classes.

Changes:

• Add metadata_field union type supporting both direct and 721-map formats
• Add RESERVE_KEYWORD_721_V4 marker for 721-style detection
• Update retrieval steps to handle both metadata formats
• Support version 4 in FT standard
• Support version 3/4 in RFT standard
• Add 721-style JSON example for NFT standard
• Update pattern descriptions with asset_name terminology
• Fix URI support to include [* bounded_bytes] for RFT

[rphair]

@thaddeusdiamond I was answering your comments by subject in alphabetical (not chronological) order, so I posted this response without seeing you've already done the proposed update:

• Proposal to Match Parity with CIP-0025 in CIP-0068 (New CIP?) #1111 (comment)

I think these changes are consistent with your suggestion of a new best-practice approach, the editorial guidelines, and the requirements of CIP-0068... but we'll follow the related issue in case other feedback indicates that a different approach should be taken. In any case we'll tag this Triage so this can all be introduced at the next CIP meeting together (to include any review or resolutions in the meantime): https://hackmd.io/@cip-editors/123

[rphair]

@thaddeusdiamond I'm recording this meeting resolution to leave this submission Unconfirmed due to a conversation that you & @Crypto2099 reportedly had about some unresolved details of implementing such a change... I'm not the best person to document this & in fact didn't catch all of it at the meeting, so I'll leave it to you & Adam to record the details here and/or discuss them in the "container" issue #1111.

[thaddeusdiamond]

I think @Crypto2099 was onboard as is since it's backwards compatible but he can comment here. Will close #1111

[rphair]

@thaddeusdiamond we might not get @Crypto2099's participation on this issue... so if there are any review points you could record here about that conversation please do... otherwise we'll continue on with this without it.

If that's the case... @Ryun1 @perturbing if you can recall any other blocking issues to consider this a CIP candidate, perhaps you can post them here? Otherwise we might mark this as Confirmed and assign a CIP number at a CIP meeting in the near future (or by editor consensus outside the meeting). @thaddeusdiamond feel free to comment again if time goes by without you observing progress along either of these lines.