refactor: add main.ts decomposition guardrails and extract core helpers

src/core/utils/electron-backend.ts

@@ -0,0 +1,39 @@
+import { CliArgs, shouldStartApp } from "../../cli/args";
+
+function getElectronOzonePlatformHint(): string | null {
+  const hint = process.env.ELECTRON_OZONE_PLATFORM_HINT?.trim().toLowerCase();
+  if (hint) return hint;
+  const ozone = process.env.OZONE_PLATFORM?.trim().toLowerCase();
+  if (ozone) return ozone;
+  return null;
+}
+
+function shouldPreferWaylandBackend(): boolean {
+  return Boolean(
+    process.env.HYPRLAND_INSTANCE_SIGNATURE || process.env.SWAYSOCK,
+  );
+}
+
+export function forceX11Backend(args: CliArgs): void {
+  if (process.platform !== "linux") return;
+  if (!shouldStartApp(args)) return;
+  if (shouldPreferWaylandBackend()) return;
+
+  const hint = getElectronOzonePlatformHint();
+  if (hint === "x11") return;
+
+  process.env.ELECTRON_OZONE_PLATFORM_HINT = "x11";
+  process.env.OZONE_PLATFORM = "x11";
+}
+
+export function enforceUnsupportedWaylandMode(args: CliArgs): void {
+  if (process.platform !== "linux") return;
+  if (!shouldStartApp(args)) return;
+  const hint = getElectronOzonePlatformHint();
+  if (hint !== "wayland") return;
+
+  const message =
+    "Unsupported Electron backend: Wayland. Set ELECTRON_OZONE_PLATFORM_HINT=x11 and restart SubMiner.";
+  console.error(message);
+  throw new Error(message);
+}