Add all Champions learnsets

[SnorlaxMonster]

Change description

Add all Pokémon Champions learnsets. Data from https://github.com/projectpokemon/champout/blob/main/masterdata/waza_learn.json

Champions is just a battle sim where you can freely swap moves around, so it doesn't really have a concept of "methods" for learning moves. My solution was to define the new pokemon_move_method "null" at index 0. If it would be preferable to make this a new positive index number, or something else entirely, let me know and I can swap it over.

Notes:

• In the game data, there are 261 entries (for 108 unique Pokémon and 61 unique moves) that are currently disabled. For example, Tsareena is currently coded to learn Magical Leaf, but Magical Leaf is disabled in Champions, so it can't actually be taught that move in-game, and if you transfer one in from HOME that knows Magical Leaf, it cannot use it. I have excluded those disabled moves from this PR, but I can add them if that would be preferred.
• Hangry Mode Morpeko is missing 5 moves that Full Belly Mode Morpeko can learn. This has no impact on gameplay, as in the Box (where you can change its moves) it is always Full Belly Mode. All of the other in-battle-only forms have the same movesets as their base forms.
  • I've just left the raw game data as-is, as there doesn't currently appear to be a way to mark this kind of discrepancy in PokeAPI. The similar (but inverted) case in Sun and Moon where Busted Form Mimikyu learns Surf via TM while Disguised Form Mimikyu does not is not currently marked either.
• Vivillon, Florges, Furfrou, Polteageist, Alcremie, and Sinistcha define separate move data for their different forms, although it is all identical. (In the case of Alcremie, Champions only defines separate learnsets for each cream, and does not distinguish between sweets.) PokeAPI does not define separate pokemon_id values for these forms, so I've had to condense these into single entries per Pokémon, but that doesn't make any functional difference.
• Mega Meowstic has the same moves as the base form of Meowstic (which has different moves depending on its gender), but PokeAPI only assigns a single pokemon_id for Mega Meowstic. Since there's no good way to mark this, I've simply not included any moves for Mega Meowstic at all.

AI coding assistance disclosure

No AI was used in the creation of this PR.

Contributor check list

• I have written a description of the contribution and explained its motivation.
• [N/A] I have written tests for my code changes (if applicable).
• I have read and understood the AI Assisted Contribution guidelines.
• I will own this change in production, and I am prepared to fix any bugs caused by my code change.