feat(property-token, registry, fractional): implement fractional owne…

[Cedarich]

Closes #37

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• Summary

• Extends the property token to support fractional ownership using ERC‑1155–style balances, enabling multiple investors to own shares of a property.

• Adds dividends, governance, and a minimal on‑chain trading flow, plus compliance hooks, portfolio aggregation, and tax reporting.

• What’s Included

• Fractional Shares

  • ERC‑1155–compatible balances per (account, token_id) with total_shares tracking
  • issue_shares, redeem_shares, transfer_shares, share_balance_of, total_shares

• Dividends

  • deposit_dividends(token_id) [payable] distributes per‑share
  • withdraw_dividends(token_id) transfers owed amounts and records tax totals

• Governance

  • create_proposal(token_id, quorum, description_hash)
  • vote(token_id, proposal_id, support) with share‑weighted voting
  • execute_proposal(token_id, proposal_id)

• Trading & Price Discovery

  • place_ask(token_id, price_per_share, amount), cancel_ask
  • buy_shares(token_id, seller, amount) [payable]; updates last_trade_price

• Compliance

  • Optional ComplianceRegistry integration; enforced in share transfers and buys

• Portfolio & Tax

  • get_portfolio(owner, token_ids) returns (token_id, shares, last_price)
  • get_tax_record(owner, token_id) returns dividends/proceeds totals

• Registry

  • enable_fractional(property_id, total_shares), get_fractional_info, is_fractional

• New Helper Module

  • contracts/fractional: aggregate_portfolio and summarize_tax utilities

• Tests

  • tests/fractional_ownership_tests.rs covers issuance/transfer, dividends, trading, governance

• Acceptance Criteria Mapping

• Design fractional token representation (ERC‑1155 compatible) — done

• Share issuance and redemption mechanisms — done

• Dividend distribution system — done

• Governance system for fractional property decisions — done

• Share trading with price discovery — done

• Compliance checks for fractional ownership — done

• Portfolio aggregation for fractional shares — done

• Tax reporting and compliance features — done

• New module and comprehensive tests — done

• Files Touched (high‑level)

• Modified: contracts/property-token/src/lib.rs

• Modified: contracts/lib/src/lib.rs

• Added: contracts/fractional/ (Cargo.toml, src/lib.rs)

• Added: tests/fractional_ownership_tests.rs

• Updated workspace: Cargo.toml members

• How to Test

• cargo test

• Backward Compatibility

• No breaking changes to existing property operations. Fractional features are additive.

• Notes / Follow‑ups

• Current trading uses native token and exact‑value buys for simplicity; can extend to order book/AMM later.

• Tax reporting tracks totals (dividends, proceeds); add cost basis if required.
  close issue Implement Fractional Ownership System #37

[LaGodxy]

LGTM