`docs/android-release.md` walks through generating the release key
with keytool, creating the debug-to-release signing lineage with
`apksigner rotate` and which capabilities the debug key keeps, the
five repository secrets, and how to check the first rotated release
on the emulators. It spells out what rotation protects and what it
does not: devices that have not updated yet, Android 7.0-8.1, which
still verify the debug-signed v2 signature, and when the lineage can
be dropped. It also covers local release builds and the `versionCode`
formula. The README links to it instead of the bare workflow file.
