refactor(errors): route fatal app errors

tests/unit/app-error-fatal-route.test.ts

@@ -0,0 +1,30 @@
+import { afterEach, describe, expect, it, vi } from "vitest";
+import { logAppError, setFatalErrorRouteForTesting } from "../../src/main/errors";
+import type { AppError } from "../../src/main/errors";
+
+describe("AppError fatal route", () => {
+  afterEach(() => {
+    setFatalErrorRouteForTesting(null);
+  });
+
+  it("routes fatal errors through the process-level handler", () => {
+    const logger = { error: vi.fn(), warn: vi.fn() };
+    const routed: AppError[] = [];
+    const sentinel = new Error("fatal route called");
+    setFatalErrorRouteForTesting((error) => {
+      routed.push(error);
+      throw sentinel;
+    });
+
+    expect(() => logAppError(logger, new Error("sqlite corrupt"), {
+      kind: "fatal",
+      code: "db.sqlite.corrupt",
+      message: "SQLite profile is corrupt",
+      context: { profile: "test" },
+    })).toThrow(sentinel);
+
+    expect(routed[0]?.kind).toBe("fatal");
+    expect(routed[0]?.code).toBe("db.sqlite.corrupt");
+    expect(logger.error).toHaveBeenCalled();
+  });
+});