Decision: leave both as default methods (option 1), not abstract. Neither
default is a live defect today — HerdrPeerLauncher is the sole single-profile
implementer and the degenerate answer (ignore role, always defaultProfile())
is correct for it. Making them abstract would force ~10 boilerplate one-line
overrides across 5 unrelated PeerLauncher test doubles (NeverSpawnsLauncher,
RaceLauncher, NoResumeLauncher, ClearContextSpyLauncher, LazyIdLauncher) that
never call either method, for a risk that is speculative (no multi-profile
HerdrPeerLauncher subclass exists or is planned).
Strengthens both javadocs with an explicit MUST-override warning and cross-
references HerdrPeerLauncher.spawn(SpawnRequest, PlacementDecision)'s existing
#450 javadoc, which already names both methods as "unoverridden here" and
ties that to being a single-profile adapter -- the concrete place a future
multi-profile launcher author would read, since #450 made that method
abstract and any subclass must write its body.
Dai Ha