Fix PanicException for single residues in connect_inter_residue()

[padix-key]

No description provided.

[codspeed-hq]

Merging this PR will degrade performance by 54.29%

⚡ 21 improved benchmarks
❌ 3 (👁 3) regressed benchmarks
✅ 73 untouched benchmarks
🆕 3 new benchmarks
⏩ 1 skipped benchmark¹

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
⚡	benchmark_bond_list_creation	815.7 µs	269.3 µs	×3
⚡	benchmark_concatenate	320.1 µs	206.4 µs	+55.08%
⚡	benchmark_connect[connect_via_distances]	26.1 ms	2.6 ms	×10
⚡	benchmark_encode	183.1 µs	156.5 µs	+17.01%
👁	benchmark_conversion[as_graph]	8.7 ms	11.8 ms	-26.16%
⚡	benchmark_connect[connect_via_residue_names]	50.6 ms	4.3 ms	×12
👁	benchmark_find_rotatable_bonds	43.9 ms	96 ms	-54.29%
⚡	benchmark_conversion[get_all_bonds]	181.1 µs	149.5 µs	+21.15%
⚡	benchmark_conversion[bond_type_matrix]	1.4 ms	1.3 ms	+10.17%
⚡	benchmark_get_all_bonds	184.8 µs	150.5 µs	+22.79%
⚡	benchmark_partial_charges	732.9 µs	142.7 µs	×5.1
⚡	benchmark_cell_list_creation	941.6 µs	336.9 µs	×2.8
🆕	benchmark_cell_list_compute_contacts[MAPPING]	N/A	18.6 ms	N/A
⚡	benchmark_get_bonds	15.3 ms	7.3 ms	×2.1
👁	benchmark_find_connected	307.3 µs	459.9 µs	-33.18%
🆕	benchmark_cell_list_compute_contacts[PAIRS]	N/A	18.5 ms	N/A
🆕	benchmark_cell_list_compute_contacts[MASK]	N/A	19.7 ms	N/A
⚡	benchmark_get_structure	20.2 ms	4 ms	×5
⚡	benchmark_get_coord	4,234.1 µs	586.6 µs	×7.2
⚡	benchmark_get_remark	757.9 µs	171.4 µs	×4.4
...	...	...	...	...

ℹ️ Only the first 20 benchmarks are displayed. Go to the app to view all benchmarks.

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_{Comparing padix-key:rust-connect-fix (9227c51) with main (2e5ef85)²}

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. ↩

2. No successful run was found on rust (d97c654) during the generation of this report, so main (2e5ef85) was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩