fix(fees): price receipt floor with wrapper and terminal reserve

[MuncleUscles]

Delivery context

Depends-On: genlayerlabs/genlayer-consensus#1692

This follows the SDK fee quote work in #214. The related qualification is genlayer-e2e #796. The paired Studio admission-floor correction is genlayer-studio #1783; these changes are qualified together through #796.

Problem and outcome

The deployed-chain fee policy fallback used a fixed 512-byte receipt when messageFeeParamsBudgetFloor() underquoted under eth_call. Consensus #1692 reserves the configured receipt wrapper plus 64 bytes of terminal output. On Nitro, a plain eth_call with zero tx.gasprice can also make both the floor view and receipt-gas view revert with InvalidRollupGasPrice. A zero chain-derived quote can incorrectly hide receipt pricing when other fees are zero.

The SDK now reads receiptWrapperBytes and useChainDerivedReceiptPrice, then calls FeeManager's gas estimate for receiptWrapperBytes + 64 with the effective receipt gas price set in the eth_call context. This respects live governance and Nitro tariff parameters without relying on a zero-price floor view. When Studio does not expose messageFeeParamsBudgetFloor, the SDK computes the same wrapper-plus-reserve floor from Studio's policy. An exposed Studio floor remains authoritative.

Implementation and validation

• Added FeeManager selectors for the wrapper, pricing mode, and receipt-gas estimate; encoded/decoded a priced, unbatched eth_call for the gas estimate.
• Reused one local receipt-floor formula for the Studio missing-floor path.
• Added regressions for the default and configured wrapper, Nitro's zero-price failure path, zero chain-derived quote with a positive network price, FeeManager gas-model changes, and Studio's explicit-floor precedence.
• npm test -- --run: 202 tests passed, no type errors.
• npm run build: ESM, CJS, and declarations passed.
• Changed-file ESLint and git diff --check: passed.

Risk and rollback

The deployed policy quote adds a priced FeeManager eth_call when receipt pricing is enabled. It requires the RPC to honor the transaction gasPrice field; viem's publicClient.call forwards that field. The required selectors are present in the v0.6 FeeManager. Reverting this commit restores the prior fallback behavior.

Checks

• I have tested this code
• I have reviewed my own PR
• I have created an issue for this PR
• I have set a descriptive PR title compliant with conventional commits

Reviewing tips

Review readCurrentFeePolicy and extractStudioFeePolicy in src/contracts/actions.ts, then the fee policy cases in tests/contracts-actions.test.ts.

User facing release notes

Fee estimates near the minimum execution budget now account for the configured receipt wrapper and Consensus terminal-output reserve.

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