feat(l1): add buckets tiers for engine_newPayload

[rodrigo-o]

Motivation

Calculate meaningful buckets for newPayload time

Description

Checklist

• Updated STORE_SCHEMA_VERSION (crates/storage/lib.rs) if the PR includes breaking changes to the Store requiring a re-sync.

Closes #issue_number

[github-actions]

Lines of code report

Total lines added: 24
Total lines removed: 0
Total lines changed: 24

Detailed view

+-----------------------------------------+-------+------+
| File                                    | Lines | Diff |
+-----------------------------------------+-------+------+
| ethrex/crates/blockchain/metrics/rpc.rs | 85    | +24  |
+-----------------------------------------+-------+------+

[rodrigo-o]

This needs to be test, i'll close it and probably reopen it in the future