Two conflicts, and the second is worth recording. main's M4 bullet gained the
Android signing decision while this branch rewrote the M5 line either side of it;
both are kept.
The other is an ADR number collision: two sessions each took 0010, one for vault
key rotation and one for Android distribution, and both are now on main. ADR
numbers are identifiers — "see ADR 0010" appears in code comments as well as in
prose — so leaving two would make every such reference ambiguous. The rotation
ADR landed first and is referenced from crypto.md, the gaps document, ADR 0009
and the sync code; the Android one is referenced from README and android-port.md.
So the later and cheaper one moves: 0010-android-distribution.md is now ADR 0011,
with its title and both references updated. Nothing about either decision changes.