Implement optimization or audit

[asg0451]

Reduce data copying in the server's add path and storage retry fallbacks to improve CPU and memory efficiency.

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[cursor]

Cursor Agent can help with this pull request. Just @cursor in comments and I'll start working on changes in this branch.
_{Learn more about Cursor Agents}

[github-actions]

Criterion benchmarks delta (ms; lower is better)

Benchmark	PR (ms)	Master (ms)	Δ (ms)	Δ (%)
e2e_rpc/rpc_add_batch_200	0.616	0.625	-0.009	-1.4%
e2e_rpc/rpc_poll_batch_200	50.878	45.106	5.772	+12.8%
e2e_rpc/rpc_remove_each_200	24.221	24.864	-0.643	-2.6%
e2e_rpc/rpc_stress_like_p2_a2_items_200	1033.702	937.106	96.596	+10.3%
storage_add/add_available_500	8.231	7.985	0.246	+3.1%
storage_poll/get_next_available_entries_500	10.999	10.902	0.097	+0.9%
storage_remove/remove_in_progress_500	20.933	19.037	1.896	+10.0%