fix(context): keep is_empty on EIP-7702 account in load_account_delegated

[cuiweixie]

Summary

• Stop overwriting AccountLoad::is_empty with the EIP-7702 delegate account's emptiness in Host::load_account_delegated.
• Align the Host default with JournalInner::load_account_delegated, so empty-account / creation-cost checks use the caller account.
• Add a regression test: non-empty EIP-7702 account delegating to an empty account must keep is_empty == false.

Test plan

• cargo test -p revm-context-interface --lib load_account_delegated_keeps_caller_is_empty_not_delegate -- --nocapture
• Confirm the test fails if account_load.data.is_empty = delegate_account.is_empty is restored

[codspeed-hq]

Merging this PR will improve performance by 3.59%

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

⚡ 1 improved benchmark
✅ 180 untouched benchmarks
⏩ 1 skipped benchmark¹

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
⚡	Simulation	blake2/2_rounds	3.4 µs	3.2 µs	+3.59%

Tip

Curious why this is faster? Comment @codspeedbot explain why this is faster on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing cuiweixie:fix/host-load-account-delegated-is-empty (c790572) with main (a094a93)}

Footnotes

1. 1 benchmark was skipped, so the baseline result was used instead. If it was deleted from the codebase, click here and archive it to remove it from the performance reports. ↩