Summary

This fixes the request/payment path so CLI wallet overrides are actually used during x402 negotiation and dry-run/payment execution.

Before this change, purl would accept --wallet and --private-key, but the runtime request flow still only used the wallet configured in ~/.purl/config.toml. In practice that caused requests like these to fail with "No wallet configured" even when the user supplied a wallet on the command line:

• purl --dry-run --private-key ... <url>
• purl --dry-run --wallet /path/to/keystore.json <url>

What changed

• apply --wallet and --private-key to the runtime Config before request execution
• add runtime-only EVM signer/address helpers in the config layer
• route EVM dry-run/address lookup through those shared helpers
• add regression coverage for:
  • --dry-run --private-key with no preconfigured wallet
  • --dry-run --wallet <path> with no preconfigured wallet

Root cause

The CLI parsed wallet override flags, but cli/src/main.rs never merged them into the config used by the request/payment flow. As a result, the negotiator still saw no available payment method unless a wallet was already configured on disk.

Verification

cargo test -q --test runtime_wallet_override_tests
cargo fmt
cargo test -q

Notes

This is intentionally narrow:

• no protocol behavior changes
• no request retry changes
• no changes to wallet file format

It only makes the existing CLI wallet override flags work in the main request path as advertised.