[Hot State] Add onchain config

[wqfish]

Note

Medium Risk
Updates the default on-chain execution config version and adds new serialized fields, which can affect genesis config generation and on-chain config compatibility if downstream components aren’t updated to understand V8.

Overview
Adds OnChainExecutionConfig::V8 and a new HotStateConfig enum (with genesis defaults) to carry hot-state tuning parameters on-chain, and switches default_for_genesis() to emit V8.

Updates forge suite genesis overrides (dag.rs, realistic_environment.rs) to handle V8 when mutating execution config fields (e.g., block_gas_limit_type, transaction_shuffler_type) so tests continue to work with the new default version.

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Cursor Bugbot has reviewed your changes and found 1 potential issue.

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Missing getter method for hot_state_config field

Medium Severity

The ExecutionConfigV8 struct adds a new hot_state_config field, but there's no corresponding pub fn hot_state_config(&self) -> HotStateConfig getter method on OnChainExecutionConfig. Every other field in the config struct (transaction_shuffler_type, block_gas_limit_type, enable_per_block_gas_limit, transaction_deduper_type, gas_price_to_burn, persisted_auxiliary_info_version) has a public getter. Without the getter, consumers of OnChainExecutionConfig cannot access the hot_state_config value through the public interface.