Partially implement Flower Gift

The Attack and Special Defense boost works, but only for the ability holder currently. It does not change Cherrim's form yet.
Also adds the necessary battler tag entries because I forgot them in the previous commit.

src/data/ability.ts

@@ -2243,7 +2243,9 @@ export function initAbilities() {
       .attr(MovePowerBoostAbAttr, (user, target, move) => move.getAttrs(RecoilAttr).length && move.id !== Moves.STRUGGLE, 1.2),
     new Ability(Abilities.MULTITYPE, "Multitype (N)", "Changes the Pokémon's type to match the Plate or Z-Crystal it holds.", 4)
       .attr(ProtectAbilityAbAttr),
-    new Ability(Abilities.FLOWER_GIFT, "Flower Gift (N)", "Boosts the Attack and Sp. Def stats of itself and allies in harsh sunlight.", 4)
+    new Ability(Abilities.FLOWER_GIFT, "Flower Gift (P)", "Boosts the Attack and Sp. Def stats of itself and allies in harsh sunlight.", 4)
+      .conditionalAttr(getWeatherCondition(WeatherType.SUNNY || WeatherType.HARSH_SUN), BattleStatMultiplierAbAttr, BattleStat.ATK, 1.5)
+      .conditionalAttr(getWeatherCondition(WeatherType.SUNNY || WeatherType.HARSH_SUN), BattleStatMultiplierAbAttr, BattleStat.SPDEF, 1.5)
       .ignorable(),
     new Ability(Abilities.BAD_DREAMS, "Bad Dreams (N)", "Reduces the HP of sleeping opposing Pokémon.", 4),
     new Ability(Abilities.PICKPOCKET, "Pickpocket", "Steals an item from an attacker that made direct contact.", 5)

src/data/enums/battler-tag-type.ts

@@ -24,6 +24,8 @@ export enum BattlerTagType {
   THUNDER_CAGE = "THUNDER_CAGE",
   PROTECTED = "PROTECTED",
   KINGS_SHIELD = "KINGS_SHIELD",
+  OBSTRUCT = "OBSTRUCT",
+  SILK_TRAP = "SILK_TRAP",
   BANEFUL_BUNKER = "BANEFUL_BUNKER",
   BURNING_BULWARK = "BURNING_BULWARK",
   ENDURING = "ENDURING",