fix(engine): use caller's gas state on precompile cache hits

[decofe]

Cached precompile results stored the full GasTracker from the original
execution, including reservoir and state_gas_spent. On cache hits, returning
that stale tracker overwrote the caller's live gas state — corrupting EIP-8037
reservoir accounting by restoring already-spent reservoir gas and zeroing
state_gas_spent.

Builds a fresh GasTracker from the caller's current gas_limit and
reservoir on cache hits, replaying only the cached regular gas cost.
Also preserves the reverted flag from the cached output.

Same fix applied to the precompile-cache example: caches only output
bytes, gas cost, and reverted flag; uses map_cacheable_precompiles
to skip identity and stateful precompiles.

Prompted by: Dragan

[github-actions]

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reth-engine-tree: patch
example-precompile-cache: patch
---

Fixed precompile cache hits to use the caller's current gas limit and reservoir instead of stale cached values, preventing corruption of EIP-8037 state gas accounting. Updated the example to store only output bytes and gas cost in the cache, reconstructing the `GasTracker` on cache hits from live caller state.

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