730e87f6

By: Tom Sydney Kerckhove <syd@cs-syd.eu>

Trim DisableMutation annotations now killed by the new mutation engine

The mutation engine auto-kills mutations that produce non-exhaustive
patterns (and prior testing work also tightened coverage), so the
RemoveCase annotations on distribute, fraction, and fromDouble's EQ
branches are now redundant, along with fromDouble's ConstBool/Cmp on
its exponent shortcut. Drop them and their justifications.

Only one disabled mutation remains: the MaybeOp on
QuantisationFactor.fromDecimalLiteral's EQ branch, where the case arm
is provably unreachable but the MaybeOp mutation does not change
pattern exhaustiveness so it cannot be auto-killed. Narrow that
annotation from {RemoveCase, MaybeOp} to just MaybeOp.

Mutation count: 374 -> 387 killed; 0 survived; 0 uncovered.
coverage-reportforwardCompatibilitymutationnixpkgs-25_11pre-commitshellconfiguredevShellreally-safe-moneyreally-safe-money-autodocodecreally-safe-money-autodocodec-genreally-safe-money-genx86_64-linux