Bump Rust 1.95, PyO3 0.28 (free-threaded), and Rust deps

[MarshalX]

No description provided.

[codspeed-hq]

Merging this PR will not alter performance

⚠️ 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

⚡ 2 improved benchmarks
❌ 2 regressed benchmarks
✅ 188 untouched benchmarks

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	test_dag_cbor_encode[roundtrip02.json]	18 µs	24.6 µs	-26.83%
⚡	Simulation	test_dag_cbor_encode[roundtrip04.json]	21.5 µs	18.9 µs	+13.99%
❌	Simulation	test_dag_cbor_encode[roundtrip16.json]	18.8 µs	21.9 µs	-14.11%
⚡	Simulation	test_dag_cbor_encode[roundtrip25.json]	24.6 µs	18.3 µs	+34.95%

Tip

Investigate this regression by commenting @codspeedbot fix this regression on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing update-rust-deps (1fa70c9) with main (e88185d)}