feat(contracts): enforce EIP-7825 gas cap in NUT bundle validation

[lumoswiz]

Description

Adds a per-transaction gas limit cap check to GenerateNUTBundle.assertValidOutput so any NUT bundle transaction whose gasLimit exceeds the EIP-7825 Osaka cap (2**24 = 16_777_216) is rejected at bundle-generation time rather than at execution.

assertValidOutput was promoted from internal to public so that tests can invoke it directly against a mutated bundle.

Tests

Full negative-path coverage for every branch in assertValidOutput was added to test/scripts/GenerateNUTBundle.t.sol. Each test follows the same pattern:

• Invoke script.run() to produce a valid bundle
• Mutate a single field (or the array length)
• Assert that script.assertValidOutput reverts with the expected error message

The count-mismatch test uses assembly to rewrite the in-memory array length rather than rebuilding the array. Shrink-only because growing would blow up the ABI encoding on the external call to assertValidOutput.

Additional context

Issue #20109 calls for two checks: the EIP-7825 upper cap and an op-geth gas floor check. This PR currently implements the upper cap only. I'm opening as a draft and plan to land the floor check in the same PR once I've synced with @0xniha on the intended approach to implementing the op-geth gas floor.

Resolved by #20075

Metadata

Closes #20109

[0xOneTony]

/ci authorize 0885ccf

[0xOneTony]

/ci authorize 51ae847