In this pull request I've changed a ton of method signatures to reflect the more-narrow types of Species, Move# and Form; additionally, I've narrowed other large collections that stored lists of species / permitted values, and reworked them to be more performant with the latest API spaghetti that PKHeX provides. Roamer met locations, usually in a range of [max-min]<64, can be quickly checked using a bitflag operation on a UInt64. Other collections (like "Is this from Colosseum or XD") were eliminated -- shadow state is not transferred COLO<->XD, so having a Shadow ID or matching the met location from a gift/wild encounter is a sufficient check for "originated in XD".
Disallow max moves from Sketch
Hide dmax moves from legal dropdown lists
Pass ushort for moves for validating memories
Internal class for move pp (hide empty class from dll users)
`Moveset` struct stores 4 moves, and exposes methods to interact with a moveset.
`IndividualValueSet` stores a 6 IV template (signed).
Performance impact:
* Less allocating on the heap: Moves - (8 bytes member ptr, 20 bytes heap->8 bytes member)
* Less allocating on the heap: IVs - (8 bytes member ptr, 28 bytes heap->8 bytes member)
* No heap pointers, no need to jump to grab data.
* Easy to inline logic for checking if moves are present (no linq usage with temporary collections).
End result is faster ctor times, less memory used, faster program.
Rewrites a good amount of legality APIs pertaining to:
* Legal moves that can be learned
* Evolution chains & cross-generation paths
* Memory validation with forgotten moves
In generation 8, there are 3 separate contexts an entity can exist in: SW/SH, BD/SP, and LA. Not every entity can cross between them, and not every entity from generation 7 can exist in generation 8 (Gogoat, etc). By creating class models representing the restrictions to cross each boundary, we are able to better track and validate data.
The old implementation of validating moves was greedy: it would iterate for all generations and evolutions, and build a full list of every move that can be learned, storing it on the heap. Now, we check one game group at a time to see if the entity can learn a move that hasn't yet been validated. End result is an algorithm that requires 0 allocation, and a smaller/quicker search space.
The old implementation of storing move parses was inefficient; for each move that was parsed, a new object is created and adjusted depending on the parse. Now, move parse results are `struct` and store the move parse contiguously in memory. End result is faster parsing and 0 memory allocation.
* `PersonalTable` objects have been improved with new API methods to check if a species+form can exist in the game.
* `IEncounterTemplate` objects have been improved to indicate the `EntityContext` they originate in (similar to `Generation`).
* Some APIs have been extended to accept `Span<T>` instead of Array/IEnumerable
