update release notes

[FabianHofmann]

Changes proposed in this Pull Request

the release notes for the header for v0.9.0 were not properly updated (still have the diff locally).

[codspeed-hq]

Merging this PR will degrade performance by 11.36%

⚠️ 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 improved benchmark
❌ 4 regressed benchmarks
✅ 170 untouched benchmarks
⏩ 175 skipped benchmarks¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Memory	test_to_lp[milp-n=50]	2 MB	2.6 MB	-23.07%
❌	Memory	test_to_lp[storage-n=250]	28.2 MB	35.6 MB	-20.63%
❌	Memory	test_to_lp[merge_balance-severity=0]	2.5 MB	3.2 MB	-20.29%
❌	Memory	test_to_lp[sos-n=1000]	2.6 MB	2.9 MB	-10.7%
⚡	Memory	test_to_lp[knapsack-n=10000]	2.8 MB	2.2 MB	+25.93%

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 doc/update-release-note-v0.9 (8b929f8) with master (78d00f9)}

Footnotes

1. 175 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[FBumann]

@FabianHofmann Im Not sure why codspeed is this flaky atm...
But I'm confident it's them, not our tests

[FabianHofmann]

@FabianHofmann Im Not sure why codspeed is this flaky atm... But I'm confident it's them, not our tests

I think we'll wait and see wether things resolve themselves