perf(bench): Add benchmarks for detrending, network analysis, and gravity

[cbueth]

This PR adds benchmarks for optimisation worth functionality:

• delta (w10/w100),
• identity,
• z_score (p1/p10)
• second_difference
• global_efficiency (un-/directed)
• transitivity
• link_density

[codspeed-hq]

Merging this PR will degrade performance by 12.17%

⚠️ 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 (👁 1) regressed benchmark
✅ 16 untouched benchmarks
🆕 11 new benchmarks

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
🆕	test_detrend_method[delta-w10]	N/A	17.5 ms	N/A
🆕	test_detrend_method[delta-w100]	N/A	17.6 ms	N/A
🆕	test_detrend_method[identity]	N/A	397.6 µs	N/A
🆕	test_detrend_method[second_difference]	N/A	246 µs	N/A
🆕	test_detrend_method[z_score-p1]	N/A	380.5 µs	N/A
🆕	test_detrend_method[z_score-p10]	N/A	1.4 ms	N/A
🆕	test_gravity	N/A	806.6 µs	N/A
🆕	test_network_metric[global_efficiency-dir]	N/A	4.3 ms	N/A
🆕	test_network_metric[global_efficiency-undir]	N/A	4.4 ms	N/A
🆕	test_network_metric[link_density]	N/A	134.2 µs	N/A
🆕	test_network_metric[transitivity]	N/A	2.1 ms	N/A
👁	test_ordinal_patterns	12.2 ms	13.8 ms	-12.17%

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_{Comparing perf/add-missing-benchmarks (471cd3a) with main (c7d03fe)}