Add Flat encoding test coverage across all packages
Pay down test coverage debt for Flat serialization instances.
This ensures encoding stability is verified by tests before
we attempt to fix the Generic derivation bug in a follow-up PR.
Adds roundtrip and stable byte encoding tests for:
- Flat library types (Maybe, Either, NonEmpty, Complex, Ratio,
Set, Tree, Map, Seq, DList, Filler, PreAligned, and
monoid/semigroup wrappers)
- TPLC types (Version, Name, Kind, DeBruijn, NamedDeBruijn,
SrcSpan, SrcSpans, DefaultFun, DefaultUni, and all newtype
wrappers including TyName, Unique, TyDeBruijn, etc.)
- PIR types (Recursivity, Strictness)
- UPLC types (Binder variants, FakeNamedDeBruijn, minimal
Program encoding)
- Value types (K encodes as ByteString, Quantity as Integer)
Also adds a standalone encoding generator executable
(cabal run flat-encoding-generator) for reproducing expected
byte constants.
