Verify random battle and capture routines against the original engine

tests/reference-parity.spec.ts

@@ -1,4 +1,4 @@
-import { test, expect, type Page } from "@playwright/test";
+import { test, expect } from "@playwright/test";
 import { existsSync, readFileSync } from "node:fs";
 import { CrystalAssets } from "../src/game/rom/assets";
 import { BattleData } from "../src/game/battle/data";
@@ -14,44 +14,7 @@ import {
 import { C } from "../src/game/battle/constants";
 import { NATIVE_MAPS } from "../src/game/rom/profile";
 import { calcStat, maxPP } from "../src/game/party/pokemon";
-import { resolve } from "node:path";
-
-const romPath = resolve(
-  process.env.CRYSTAL_ROM_PATH ??
-    "Pokemon - Crystal Version (UE) (V1.1) [C][!].gbc",
-);
-const symbolsPath = ".reference/pokecrystal/pokecrystal11.sym";
-
-/** Banked addresses from the private PRET rebuild's symbol file. */
-function loadSymbols() {
-  const symbols = new Map(
-    readFileSync(symbolsPath, "utf8")
-      .split("\n")
-      .flatMap((line) => {
-        const match = /^([0-9a-f]{2}):([0-9a-f]{4}) (\S+)$/.exec(line);
-        return match
-          ? [[match[3], { bank: parseInt(match[1], 16), address: parseInt(match[2], 16) }] as const]
-          : [];
-      }),
-  );
-  return {
-    at: (name: string) => symbols.get(name)!.address,
-    routine: (name: string) => symbols.get(name)!,
-  };
-}
-
-/** Open the reference page and hand it the ROM through an isolated file
- * input, without an HTTP ROM endpoint. */
-async function openReference(page: Page) {
-  await page.goto("/reference.html");
-  await page.evaluate(() => {
-    const input = document.createElement("input");
-    input.type = "file";
-    input.id = "reference-fixture";
-    document.body.append(input);
-  });
-  await page.locator("#reference-fixture").setInputFiles(romPath);
-}
+import { romPath, symbolsPath, loadSymbols, openReference } from "./reference-fixture";
 
 test("native decompression matches original GB assembly executing in the reference emulator", async ({
   page,