Update PyO3 to 0.29

[musicinmybrain]

https://pyo3.rs/main/changelog.html#0290---2026-06-11

Fixes:

• https://rustsec.org/advisories/RUSTSEC-2026-0176.html
• https://rustsec.org/advisories/RUSTSEC-2026-0177.html

[codspeed-hq]

Merging this PR will degrade performance by 13.02%

⚠️ 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

❌ 6 regressed benchmarks
✅ 15 untouched benchmarks

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
❌	test_benchmark_unpacking_all_without_mtime_using_fastar[uncompressed]	24.6 ms	28.5 ms	-13.95%
❌	test_benchmark_unpacking_all_with_fastar[uncompressed]	24.8 ms	28.7 ms	-13.78%
❌	test_benchmark_unpacking_all_without_mtime_using_fastar[gzip_compressed]	27.6 ms	31.6 ms	-12.8%
❌	test_benchmark_unpacking_all_with_fastar[gzip_compressed]	27.8 ms	31.8 ms	-12.79%
❌	test_benchmark_unpacking_all_without_mtime_using_fastar[zstd_compressed]	28.3 ms	32.4 ms	-12.45%
❌	test_benchmark_unpacking_all_with_fastar[zstd_compressed]	28.5 ms	32.6 ms	-12.34%

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 musicinmybrain:pyo3-0.29 (5c020bd) with main (e332d83)}