Add isolated token-to-token pool

[KevinMehrabi]

Summary

• add a standalone, asset-agnostic FA2-to-FA2 constant-product pool
• fix fees at 25 bp for liquidity providers and 5 bp for the protocol
• integrate LP accounting and permanently lock the minimum initial liquidity
• verify every underlying transfer against authenticated before/after pool balances
• add pause-safe withdrawals, separate protocol-fee accounting, and two-step administrator handoff
• add environment-only deployment tooling with an offline Michelson storage-encoding test and an explicit mainnet confirmation guard
• add scoped CI, deployment documentation, and an internal security review

Why

The repository needs a token-to-token pool that does not inherit unrelated native-XTZ, baker, auction, reward-bucket, flash-loan, or multi-pair custody responsibilities. This implementation isolates one immutable FA2 pair per deployment and keeps all live token, administrator, fee-recipient, and metadata values outside source control.

Validation

• LIGO 1.11.5 compilation reproduced the checked-in Michelson byte-for-byte
• compiled artifact SHA-256: e80be7e08aed3782c338472d1faa578d73719414f2b80254a10df5c7300f6268
• encoded contract size: 18,999 bytes
• 12 end-to-end LIGO tests pass
• TypeScript type checking passes
• 7 deployment/configuration tests pass, including compiled-schema storage encoding
• npm ci --ignore-scripts succeeds
• npm audit --omit=dev --audit-level=moderate reports zero vulnerabilities for the deployment package

Review and deployment gates

This remains a draft pending independent source and Michelson review. Before mainnet deployment:

• reproduce and approve the exact compiled artifact
• allowlist the exact two non-taxed FA2 contracts, token IDs, callback behavior, and administrative controls
• rehearse initialization, swaps in both directions, deposits, withdrawals, fee claims, pause behavior, and administrator acceptance on testnet
• confirm the final administrator and immutable fee recipient on-chain
• confirm UI/router pool allowlisting, deadline handling, and minimum-output handling

The integrated LP entrypoints intentionally accept singleton requests rather than advertising batch-complete FA2 behavior.