Port the special battle types and contest battles

Run the forced-shiny, trap, forced-item, Celebi, Suicune, roaming and Bug-Catching Contest battle types. Roaming battles keep their struct's DVs and HP byte, and every other battle makes CleanUpBattleRAM's roaming roll. The contest shows PARKBALL×, counts down Park Balls, ends when they run out, keeps its catch outside the party and asks before switching. Scripts load the special types with loadvar, and while a contest runs, encounters use BugCatchingContestBattleScript and ContestMons.

Validated with 596 unit tests, 155 browser tests (including the contest menu and switch screen), native/reference builds and reference/vendor/release checks. National Park's contest event, the roaming release and the Ilex Forest Celebi event come with their maps.

Closes #28

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/game/rom/profile.ts

@@ -160,6 +160,7 @@ export const RAM = {
   curHPAnimDeltaHP: 0xd1f3,
   visitedSpawns: 0xdca5,
   tempWildMonSpecies: 0xd22e,
+  parkBallsRemaining: 0xdc79,
   coins: 0xd855,
   /** hBGMapMode: HRAM, like hMoneyTemp below. */
   bgMapMode: 0xffd4,
@@ -193,6 +194,8 @@ export const ENGINE_FLAGS = {
 /** Overworld scripts, routines and tables, keyed by their PRET labels so
  * that `npm run check:reference` verifies each address by name. */
 export const OVERWORLD = {
+  BugCatchingContestBattleScript: 0x135eb,
+  ContestMons: 0x97d87,
   "OverworldTownMap": 0xc2c0,
   "TownMapGFX": 0xf8ba0,
   "JohtoMap": 0x91fff,
@@ -593,6 +596,10 @@ export const BATTLE = {
   "HeavyBall_GetDexEntryBank.PokedexEntryBanks": 0xec4c,
   "HeavyBallMultiplier.WeightsTable": 0xecc4,
   FleeMons: 0x3c59a,
+  WildCelebiAppearedText: 0x80793,
+  ContestAskSwitchText: 0xcc0c2,
+  "DisplayAlreadyCaughtText.ContestAlreadyCaughtText": 0xcc0d0,
+  "BugContest_SetCaughtContestMon.ContestCaughtMonText": 0xe71d,
 
   DownpourText: 0x817a3,
   SunGotBrightText: 0x817b8,