Add CIP-179 survey links to governance metadata creation

[Cerkoryn]

Summary

Adds CIP-179 survey linkage to metadata-create.sh.

• Accepts --cip179-survey-ref [#index]
• Offers an optional interactive prompt for terminal users
• Adds the required body.cip179 object and JSON-LD context
• Validates and normalizes the survey transaction reference
• Leaves existing non-interactive workflows unchanged

This also adds a checked --network <mainnet|preprod|preview> path for resolving the governance action deposit without a local node. The script requires independent parameter sources to agree and rejects
network/address mismatches rather than accepting a manually entered deposit.

Validation

• Shell syntax checks pass
• Generated metadata was validated as CIP-108/CIP-169 JSON-LD
• CIP-179 survey references use the v5 survey-link structure
• Existing local-node deposit resolution remains supported