Add node_list option to adjacency_matrix

[techyangj]

Closes #1411.

This adds an optional node_list argument to adjacency_matrix, graph_adjacency_matrix, and digraph_adjacency_matrix. The argument controls the output matrix row and column order and can be used to build a matrix for a subset of graph nodes.

Testing done:

• cargo fmt --check
• git diff --check
• From tests/: python -m unittest graph.test_adjacency_matrix digraph.test_adjacency_matrix test_dispatch (85 tests)

Disclosure: I used AI assistance while preparing this patch, then reviewed the diff and validated it locally.

• I ran rustfmt locally
• I have added the tests to cover my changes.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.

[CLAassistant]

All committers have signed the CLA.

[coveralls]

Coverage Report for CI Build 26157815024

Coverage decreased (-0.002%) to 94.72%

Details

• Coverage decreased (-0.002%) from the base build.
• Patch coverage: 52 of 52 lines across 1 file are fully covered (100%).
• 3 coverage regressions across 1 file.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

3 previously-covered lines in 1 file lost coverage.

File	Lines Losing Coverage	Coverage
rustworkx-core/src/generators/random_graph.rs	3	86.73%

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Coverage Stats

Relevant Lines:	20190
Covered Lines:	19124
Line Coverage:	94.72%
Coverage Strength:	925112.03 hits per line

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💛 - Coveralls