add new subtypes, detailed benchmarks

[gokutheengineer]

This pull request introduces comprehensive benchmarking and memory profiling for various hash map implementations used in the project, comparing dolthub, cockroachdb, Go's native map, and tidwall. It also adds the necessary dependencies for benchmarking, and includes a minor thread-safety improvement. The results are summarized in a new markdown report and detailed output files, providing actionable recommendations for map selection based on performance and memory usage.

Benchmarking and Analysis

• Added a detailed benchmark report (BENCHMARK_REPORT.md) comparing four hash map implementations across Put, Get, Exists, Delete operations, and memory footprint. The report includes recommendations and key takeaways for map selection.
• Added benchmark result files for Put, Get, Exists, Delete operations, and memory footprint for all map types and implementations (res_put_ops.txt, res_get_ops.txt, res_exists_ops.txt, res_del_ops.txt, res_memory_footprint.txt). [1] [2] [3] [4] [5]

Dependency Management

• Updated go.mod to add indirect dependencies for benchmarking and alternative map implementations: cockroachdb/swiss, klauspost/cpuid/v2, tidwall/hashmap, and zeebo/xxh3.

Thread Safety Improvement

• Changed SwissMapUint64.Exists method to use a read lock (RLock) instead of a write lock (Lock), improving concurrency for read operations.

Miscellaneous

• Removed the package declaration from tx_map_examples_test.go, likely as a cleanup or to avoid conflicts in test files.

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These changes provide valuable insights into the trade-offs between speed and memory usage for different map implementations, and improve the thread safety of the codebase.

[github-actions]

👋 Thanks, @gokutheengineer!

This pull request comes from a fork. For security, our CI runs in a restricted mode.
A maintainer will triage this shortly and run any additional checks as needed.

• 🏷️ Labeled: fork-pr, requires-manual-review
• 👀 We'll review and follow up here if anything else is needed.

Thanks for contributing to bsv-blockchain/go-tx-map! 🚀

[sonarqubecloud]

Quality Gate failed

Failed conditions
3.7% Duplication on New Code (required ≤ 3%)

See analysis details on SonarQube Cloud

[mrz1836]

Linter and pre-commit issues. Please review the CI errors. @gokutheengineer