fix: eth_simulateV1 future blocks and validation error

[macfarla]

PR description

• Return BLOCK_NOT_FOUND error instead of null success response when eth_simulateV1 is called with a future/unknown block number, per the execution-apis spec
• Map UPFRONT_COST_EXCEEDS_BALANCE (-38014) error code to -32602 (invalid params) when validation is enabled, per the execution-apis spec. When validation is not enabled, the original -38014 code is preserved.

Fixed Issue(s)

Ref #9636
fixes #9829

Hive rpc-compat tests fixed (6)

• eth_simulateV1/ethSimulate-empty-with-block-num-set-plus1
• eth_simulateV1/ethSimulate-make-call-with-future-block
• eth_simulateV1/ethSimulate-gas-fees-and-value-error-38014-with-validation
• eth_simulateV1/ethSimulate-simple-no-funds-with-validation
• eth_simulateV1/ethSimulate-simple-no-funds-with-validation-without-nonces
• eth_simulateV1/ethSimulate-simple-send-from-contract-with-validation

Thanks for sending a pull request! Have you done the following?

• Checked out our contribution guidelines?
• Considered documentation and added the doc-change-required label to this PR if updates are required.
• Considered the changelog and included an update if required.
• For database changes (e.g. KeyValueSegmentIdentifier) considered compatibility and performed forwards and backwards compatibility tests

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?

[Copilot]

Pull request overview

Updates eth_simulateV1 to align with execution-apis spec behavior for future blocks and validation-related error codes.

Changes:

• Return BLOCK_NOT_FOUND instead of a null success when simulating against a future/unknown block.
• Map UPFRONT_COST_EXCEEDS_BALANCE (-38014) to -32602 (invalid params) when validation is enabled.
• Update unit test expectations and document the behavior change in the changelog.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
ethereum/api/src/test/java/org/hyperledger/besu/ethereum/api/jsonrpc/internal/methods/EthSimulateV1Test.java	Updates test to expect BLOCK_NOT_FOUND error for future block numbers.
ethereum/api/src/main/java/org/hyperledger/besu/ethereum/api/jsonrpc/internal/methods/EthSimulateV1.java	Implements error mapping for validation and converts null-success responses to BLOCK_NOT_FOUND.
CHANGELOG.md	Notes the RPC behavior changes as breaking changes.

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