docs: record release maintenance lessons

[albert20260301]

Summary

• record the Kotlin Release Please incompatibility as a maintainer-decision boundary
• record the required registry-verification and 24-hour escalation rule

Validation

• make lint ✅
• git diff --check ✅
• make check-links ⚠️ not run: lychee is not installed in this environment

[albert20260301]

@redox could you review this?

I picked you because you authored and approved the most recent MEMORY.md change. CI validation is green locally for Markdown lint and diff checks; the link check could not run because lychee is unavailable here. The main review focus is whether these are the right durable boundaries for release maintenance.

[redox]

not sure it brings much value to your memory

[albert20260301]

Agreed. I will not retain these as durable memory; the closed PR provides the audit trail.