Fixed - logging cleanup for invalid blocks #10160

[sagarkhandagre998]

PR description

Logging cleanup: demote invalid-block ERROR noise to DEBUG in block processors

AbstractBlockProcessor was logging at ERROR for block validation failures (state-root mismatch, blob gas mismatch, requests/BAL hash mismatch, etc.). These are expected outcomes when the network sends a genuinely invalid block — not Besu errors. MainnetBlockValidator.handleFailedBlockProcessing already owns the canonical INFO-level "Invalid block …" message for all failure paths, making the ERROR logs both wrong-level and redundant.

The state-root mismatch ERROR was additionally duplicated: the parallel attempt fired it, the sequential fallback fired it again, and then the validator emitted its INFO line — three log entries for one invalid block.

Changes:

• All LOG.error calls in AbstractBlockProcessor.processBlock demoted to LOG.debug.
• MainnetParallelBlockProcessor fallback log is now conditional:
  • causedBy().isPresent() → keeps LOG.info (a real local exception occurred in the parallel path)
  • causedBy().isEmpty() → LOG.debug (deterministic block invalidity; the validator's INFO line is sufficient)

Result for a genuine invalid network block:

DEBUG AbstractBlockProcessor  – failed persisting block due to stateroot mismatch …
DEBUG MainnetParallelBlockProcessor – Parallel transaction processing reported block invalid. Falling back …
DEBUG AbstractBlockProcessor  – failed persisting block due to stateroot mismatch …
INFO  MainnetBlockValidator   – Invalid block 24788495 (0x1048…): World State Root does not match …
WARN  AbstractEngineNewPayload – Invalid new payload: …

Fixed Issue(s)

Fixed #10160

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Locally, you can run these tests to catch failures early:

• spotless: ./gradlew spotlessApply
• unit tests: ./gradlew build
• acceptance tests: ./gradlew acceptanceTest
• integration tests: ./gradlew integrationTest
• reference tests: ./gradlew ethereum:referenceTests:referenceTests
• hive tests: Engine or other RPCs modified?

[sagarkhandagre998]

@jframe kindly review