[LABS-305] Extract signing functionality from wallet RPC to its own library

[Quexington]

This PR removes the signing logic that was previously only accessible from the RPC into its own library. This minimizes the RPC logic and also provides this functionality to other wallet areas potentially.

(it also adds tests for the previously untested sign_message_by_id)

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Note

Extracts message signing/verification into a shared util and refactors RPC and wallets to use it; adds tests for signing by NFT ID and address.

• Wallet signing refactor:
  • Introduce chia/wallet/util/signing.py with sign_message() and verify_signature().
  • Remove ad-hoc sign_message methods from Wallet, DIDWallet, and NFTWallet; add helpers like convert_secret_key_to_synthetic() and current_p2_puzzle_hash().
• RPC updates:
  • wallet_rpc_api.py: delegate verify_signature, sign_message_by_address, and sign_message_by_id to new signing util; simplify key retrieval and signing flow.
  • wallet_request_types.py: add signing_mode_enum helpers and properties; extend request/response types for signing.
• Tests:
  • Add test_sign_message_by_nft_id (NFT signing across modes) and test_sign_message_by_address.
  • Update imports/usages accordingly.

^{Written by Cursor Bugbot for commit 3d85e99. This will update automatically on new commits. Configure here.}

[github-actions]

File	Coverage	Missing Lines
chia/wallet/did_wallet/did_wallet.py	66.7%	lines 906
chia/wallet/util/signing.py	93.5%	lines 35, 37, 39
chia/wallet/wallet_request_types.py	91.3%	lines 387-388

Total	Missing	Coverage
135 lines	6 lines	95%

[coveralls-official]

Pull Request Test Coverage Report for Build 19944879525

Details

• 129 of 135 (95.56%) changed or added relevant lines in 8 files are covered.
• 42 unchanged lines in 9 files lost coverage.
• Overall coverage decreased (-0.02%) to 90.753%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
chia/wallet/did_wallet/did_wallet.py	2	3	66.67%
chia/wallet/wallet_request_types.py	21	23	91.3%
chia/wallet/util/signing.py	43	46	93.48%

Files with Coverage Reduction	New Missed Lines	%
chia/_tests/simulation/test_simulation.py	1	96.47%
chia/timelord/timelord_api.py	1	93.02%
chia/wallet/wallet_node.py	1	86.91%
chia/_tests/core/test_farmer_harvester_rpc.py	2	98.06%
chia/timelord/timelord_launcher.py	2	70.0%
chia/full_node/full_node.py	4	87.0%
chia/daemon/server.py	7	80.62%
chia/timelord/timelord.py	11	72.0%
chia/server/node_discovery.py	13	79.79%

Totals
Change from base Build 19938390251:	-0.02%
Covered Lines:	102485
Relevant Lines:	112753

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💛 - Coveralls

[prozacchiwawa]

makes sense. that was a fair amount of duplication in the individual wallet code.

[emlowe]

cursor review