Add scripted trainer battle foundation and native move AI

tests/trainer-browser.spec.ts

@@ -0,0 +1,63 @@
+import { test, expect } from "@playwright/test";
+import { existsSync, readFileSync } from "node:fs";
+import { resolve } from "node:path";
+
+const romPath = resolve(process.env.CRYSTAL_ROM_PATH ?? "Pokemon - Crystal Version (UE) (V1.1) [C][!].gbc");
+test.beforeEach(() => test.skip(!existsSync(romPath), "Requires the local user ROM; trainer script is a test fixture."));
+
+test("trainer UI refuses RUN, wins against Joey and saves the reward", async ({ page }) => {
+  // Route substitution stays in the test harness; production imports no fixture.
+  await page.route("**/src/game/runtime.ts", async (route) => {
+    const response = await route.fetch();
+    const source = await response.text();
+    const needle = "const world = new GameWorld(assets);";
+    expect(source).toContain(needle);
+    await route.fulfill({ response, body: source.replace(needle,
+      `const { trainerFixtureWorld } = await import('/tests/trainer-fixture.ts');
+       const world = trainerFixtureWorld(assets, undefined, false, true);`) });
+  });
+  await page.clock.install({ time: new Date("2026-09-22T12:00:00") });
+  await page.goto("/");
+  await page.locator("#rom-file").setInputFiles(romPath);
+  await expect(page.locator("#status")).toContainText("verified");
+  await page.clock.pauseAt(new Date("2026-09-22T12:05:00"));
+  await page.locator("#play").click();
+  await page.keyboard.press("KeyX");
+  await expect(page.locator("#battle")).toBeVisible();
+  await expect(page.locator("#battle-foe-name")).toHaveText("RATTATA");
+  let triedRun = false;
+  const messages = new Set<string>();
+  for (let guard = 0; guard < 60; guard++) {
+    if (!(await page.locator("#battle").isVisible())) break;
+    messages.add(await page.locator("#battle-text").innerText());
+    const menu = page.locator("#battle-menu");
+    const fight = menu.getByRole("button", { name: "FIGHT", exact: true });
+    if (await fight.count()) {
+      if (!triedRun) {
+        triedRun = true;
+        await menu.getByRole("button", { name: "RUN", exact: true }).click();
+      } else {
+        await fight.click();
+        await menu.getByRole("button", { name: /TACKLE/ }).click();
+      }
+    } else if (await menu.getByRole("button", { name: /Continue/ }).count()) {
+      await menu.getByRole("button", { name: /Continue/ }).click();
+    } else await page.clock.runFor(1200);
+  }
+  await expect(page.locator("#battle")).toBeHidden();
+  await expect(page.locator("#game-notice")).toHaveText("");
+  const shown = [...messages].join("\n");
+  expect(shown).toContain("JOEY");
+  expect(shown).toMatch(/No!.*running/s);
+  expect(shown).toContain("Ack! I lost again!");
+  expect(shown).toContain("64");
+  await page.locator("#tab-saves").click();
+  const download = page.waitForEvent("download");
+  await page.locator("#backup").click();
+  const path = (await (await download).path())!;
+  const record = JSON.parse(readFileSync(path, "utf8"));
+  const state = JSON.parse(Buffer.from(record.state, "base64").toString("utf8"));
+  expect(state.money).toBe(3064);
+  expect(state.pokedex.seen).toContain(19);
+  expect(state.events).toContain(256);
+});