feat(erc7730): serve signed definition catalogs - #93

Summary

• add an untrusted host-side catalog for signed compiled ERC-7730 envelopes
• preload root definitions through the authenticated device protocol
• answer device-driven definition requests by exact lookup tuple or definition ID
• support recursive child lookup and parent replay requests during Ethereum signing
• fail closed on unknown, ambiguous, oversized, or over-depth requests

Verification

• ERC-7730 protocol and catalog tests: 6 passed
• Python compilation succeeds
• uses the canonical protocol commit already pinned by firmware alpha