chore: Remove err from instrument on tx_template.prep_entries

[jirijakes]

This caused an unnecessary alert. This should be handled by higher-level function and not by private low-level one.

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Note

Low Risk
Low risk: this only adjusts tracing::instrument behavior to stop emitting error-level events from a private helper, with no functional or data-path changes.

Overview
Removes the err flag from the #[instrument] annotation on tx_template.prep_entries, so errors returned by this low-level helper are no longer automatically recorded/emitted by that span.

This shifts error reporting responsibility to higher-level callers and should reduce noisy alerts without changing transaction/entry preparation logic.

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[github-actions]

📊 Performance Report

Commit: bee7d67
Updated: 2026-05-01 11:00:13 UTC

Cala Performance Benchmark Results (non-representative)

Criterion Benchmark Results (single-threaded)

Benchmark	Time per Run	Throughput	% vs Baseline
post_simple_transaction	6.508ms	153 tx/s	0 (baseline)
post_and_recalculate_ec_account_set	18.517ms	54 tx/s	-184.0%
post_and_batch_recalculate_ec_account_set	13.259ms	75 tx/s	-103.0%
post_multi_layer_transaction	7.093ms	140 tx/s	-8.0%
post_simple_transaction_with_effective_balances	8.405ms	118 tx/s	-29.0%
post_simple_transaction_with_skipped_velocity	6.682ms	149 tx/s	-2.0%
post_simple_transaction_with_velocity	8.532ms	117 tx/s	-31.0%
post_simple_transaction_with_hit_velocity	3.704ms	269 tx/s	+43.0%
post_simple_transaction_with_one_account_set	6.150ms	162 tx/s	+5.0%
post_simple_transaction_with_five_account_sets	7.354ms	135 tx/s	-12.0%
post_simple_transaction_with_ec_account_set	6.015ms	166 tx/s	+7.0%

Load Testing Results (parallel-execution)

Scenario	tx/s
1 parallel	96.25
2 parallel	133.37
5 parallel	172.34
10 parallel	173.00
20 parallel	168.71
2 contention	130.80
5 contention	149.55
2 acct_sets	117.15
5 acct_sets	134.01

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Note: Performance results may vary based on system resources and database state.

Last updated by commit bee7d67