Move the bytecode RECORD rationale to installation

[zaniebot]

Move the PEP 491 and RECORD explanation from the generic compilation helper to the pip installation path that selects newly installed Python sources. This keeps the helper focused on scheduling work and places the rationale next to the behavior it explains.

[zanieb]

@zsol honestly not sure what you are looking for here. I think the naive change here is worse. I don't see any issue with the comment as-is after looking a second time? It's not user-facing, it's internal doc commentary.

[codspeed-hq]

Merging this PR will degrade performance by 19.88%

⚠️ 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
❌ 5 regressed benchmarks
✅ 7 untouched benchmarks
⏩ 11 skipped benchmarks¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	resolve_warm_airflow	490.4 ms	868.2 ms	-43.51%
❌	Simulation	resolve_warm_jupyter	48.3 ms	84.1 ms	-42.57%
❌	Simulation	resolve_warm_jupyter_universal	157.5 ms	215.5 ms	-26.92%
❌	WallTime	resolve_warm_airflow	375.9 ms	441.2 ms	-14.81%
❌	WallTime	resolve_warm_jupyter_universal	123.9 ms	139.9 ms	-11.5%
⚡	Simulation	unzip_wheel_many_files	87.5 ms	78 ms	+12.16%
⚡	Simulation	prepare_wheel_many_files	108.7 ms	102.8 ms	+5.72%

Tip

Investigate this regression with the CodSpeed MCP and your agent.

---

_{Comparing zaniebot:zb/bytecode-record-doc (917d272) with main (bc286d3)²}

Footnotes

1. 11 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. ↩

2. No successful run was found on zb/bytecode-timeout-doc (ac8a461) during the generation of this report, so main (bc286d3) was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩