Switch release flow from release-plz to Vortex-style release-drafter

[joseph-isaacs]

Replace release-plz with the release process used by vortex-data/vortex,
adapted to onpair's single-crate, crates.io-only setup:

• release-drafter.yml + .github/release-drafter.yml: maintain a draft
  GitHub Release on every push to develop, with the next version and
  categorized notes resolved from changelog/* PR labels.
• labels.yml: enforce exactly one changelog/* label per PR.
• publish.yml: on release published, set the crate version from the tag
  and publish to crates.io.

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[codspeed-hq]

Merging this PR will not alter performance

⚠️ Unknown Walltime execution environment detected

Using the Walltime instrument on standard Hosted Runners will lead to inconsistent data.

For the most accurate results, we recommend using CodSpeed Macro Runners: bare-metal machines fine-tuned for performance measurement consistency.

⚠️ 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

⚡ 4 improved benchmarks
❌ 3 regressed benchmarks
✅ 25 untouched benchmarks
⏩ 2 skipped benchmarks¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	WallTime	decompress_all[12]	706.7 µs	886.9 µs	-20.32%
❌	WallTime	decompress_all[16]	723.3 µs	886 µs	-18.37%
❌	WallTime	decompress_all[("p_name", 12)]	1.2 ms	1.4 ms	-13.34%
⚡	WallTime	decompress_all[("l_comment", 16)]	24.5 ms	19 ms	+28.69%
⚡	WallTime	decompress_all[("o_comment", 16)]	21.2 ms	17.2 ms	+23.53%
⚡	WallTime	decompress_all[("o_comment", 12)]	20.2 ms	16.8 ms	+19.87%
⚡	WallTime	decompress_all[("l_comment", 12)]	22.1 ms	19 ms	+16.45%

Tip

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

---

_{Comparing claude/vortex-release-onpair-zTgTT (388c36a) with develop (a6c11b2)}

Footnotes

1. 2 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. ↩