test(e2e): make reactor-layout spec project-independent

The spec hardcoded vanilla-Py reactor numbers (2 GW breeder → 3 reactors,
2×2 → 1), so it failed on a py-hard-mode active project where the breeder
is 10 GW (→ 0.6 reactors) and heat has several producers behind a picker
dialog instead of a single-candidate auto-add.

Assert the INVARIANT instead: the breeder's neighbour_bonus (1 → ×3 heat at
2×2) is a Py constant, so read the base reactor count at runtime and check
the 2×2 farm both shows '×3 heat' and drops the count to a third — true in
any Py config. Also handle the multi-candidate heat picker (wait for it,
pick the breeder) and drop an unused import.

Closes #122

Author: ApocDev

app/e2e/mut/reactor-layout.e2e.ts

@@ -1,11 +1,18 @@
 import { expect, test } from "@playwright/test";
-import { createBlock, goalRateButton, goto } from "./helpers";
+import { createBlock, goalRateButton } from "./helpers";
 
 /**
  * Reactor neighbour bonus (#94): a heat block's reactor row carries a farm
- * layout chip. Picking 2×2 scales each reactor's heat output ×3 (Py's breeder
- * reactor has neighbour_bonus 1 = +100% per adjacent working reactor), so the
- * solved reactor count drops to a third — and the choice persists.
+ * layout chip. Picking 2×2 gives each reactor 2 working neighbours → Py's
+ * breeder reactor (neighbour_bonus 1 = +100% each) makes ×3 heat, so the solved
+ * reactor count drops to a third — and the choice persists.
+ *
+ * Project-independent (#122): the breeder's ×3 bonus is a Py constant, but its
+ * raw power (hence the absolute reactor count) differs between mod configs
+ * (2 GW in vanilla Py, 10 GW in py-hard-mode). So assert the INVARIANT — the
+ * ×3 layout bonus and a strictly lower count — with the base count read at
+ * runtime, not hardcoded. The heat goal also has several producers in some
+ * configs, so pick the breeder from the picker when one opens.
  */
 test("reactor row: picking a 2×2 farm scales heat ×3 and persists", async ({ page }) => {
   await createBlock(page);
@@ -23,32 +30,45 @@ test("reactor row: picking a 2×2 farm scales heat ×3 and persists", async ({ p
   await rateInput.press("Enter");
   await expect(goalRateButton(page)).toHaveText("6 GW");
 
-  // the goal is unmade — click its icon to add the producing recipe (a single
-  // candidate — the breeder-reactor heat recipe — is auto-added, no dialog)
+  // click the goal icon to add a producer: one heat candidate auto-adds, several
+  // open a picker — pick the breeder reactor either way
   await page.locator('button[title^="click to add a recipe that makes this goal"]').click();
+  // the picker opens asynchronously (multi-candidate configs); give it a beat to
+  // appear, then pick the breeder. A single-candidate config auto-adds — no dialog.
+  const heatPicker = page.getByRole("dialog", { name: /Recipes that make/ });
+  await heatPicker.waitFor({ state: "visible", timeout: 2000 }).catch(() => {});
+  if (await heatPicker.isVisible().catch(() => false)) {
+    await heatPicker.getByRole("button", { name: /Breeder reactor heat/ }).click();
+    await expect(heatPicker).toBeHidden();
+  }
+  // the reactor row is in the grid now
   await expect(page.getByText("Breeder reactor heat")).toBeVisible();
 
-  // flat-rated (1×1): 6 GW ÷ 2 GW per reactor = 3 reactors, chip shows no bonus.
-  // The building count is now its own click-to-fix field (#121) beside the
-  // machine icon — unpinned here, so it carries the "click to fix" title.
+  // flat-rated (1×1): some whole+fraction of reactors, chip shows no bonus. The
+  // building count is its own click-to-fix field (#121) beside the machine icon.
   const machineChip = page.locator('button[title="click to fix the building count"]');
-  await expect(machineChip).toContainText("3");
+  await expect(machineChip).toBeVisible();
+  const baseCount = Number((await machineChip.textContent())?.trim());
+  expect(baseCount).toBeGreaterThan(0);
   const layoutChip = page.locator('button[title^="reactor farm"]');
   await expect(layoutChip).toContainText("1×1");
   await expect(layoutChip).not.toContainText("heat");
 
-  // pick a 2×2 farm: each reactor gains 2 neighbours → ×3 heat → 1 reactor
+  // pick a 2×2 farm: each reactor gains 2 neighbours → ×3 heat → a third the count
   await layoutChip.click();
   await page.getByRole("menuitem", { name: /^2×2/ }).click();
   await expect(layoutChip).toContainText("2×2");
   await expect(layoutChip).toContainText("×3 heat");
-  await expect(machineChip).toContainText("1");
+  const bonusCount = Number((await machineChip.textContent())?.trim());
+  expect(bonusCount).toBeCloseTo(baseCount / 3, 2);
 
   // outlive the editor's 700ms auto-save debounce, then reload: the layout
   // (and the rescaled count) persisted with the block doc
   await page.waitForTimeout(1200);
   await page.reload();
   await expect(layoutChip).toContainText("2×2");
   await expect(layoutChip).toContainText("×3 heat");
-  await expect(machineChip).toContainText("1");
+  await expect(machineChip).toBeVisible();
+  const persisted = Number((await machineChip.textContent())?.trim());
+  expect(persisted).toBeCloseTo(bonusCount, 2);
 });