chore: finish frontend ESLint migration #18

Enable every plugin recommended preset and replace Biome with ESLint formatting.

Preserve API contracts and JSX whitespace; verify source, tests, builds and tooling.

src/app/routes/RouteErrorBoundary/RouteErrorBoundary.test.tsx

@@ -3,11 +3,14 @@ import { fireEvent, render, screen } from "@testing-library/react";
 import { type FC, lazy, Suspense } from "react";
 import { MemoryRouter, useLocation, useNavigate } from "react-router";
 import { describe, expect, it, vi } from "vitest";
+
 import { RouteErrorBoundary } from "./RouteErrorBoundary";
 
-let authenticated = false;
+const session = { isAuthenticated: false };
 vi.mock("@/features/auth", () => ({
-	useAuth: () => ({ user: authenticated ? {} : null }),
+	useAuth: () => ((/* eslint-disable unicorn/no-null -- Fixture preserves the production contract’s explicit null values. */
+		{ user: session.isAuthenticated ? {} : null }
+		/* eslint-enable unicorn/no-null */)),
 }));
 
 const ThrowingRoute: FC = () => {
@@ -17,11 +20,13 @@ const ThrowingRoute: FC = () => {
 const HealthyRoute: FC = () => {
 	return (
 		<div>
-			{useLocation().pathname === "/healthy" ? (
-				"healthy route"
-			) : (
-				<ThrowingRoute />
-			)}
+			{useLocation().pathname === "/healthy"
+				? (
+						"healthy route"
+					)
+				: (
+						<ThrowingRoute />
+					)}
 		</div>
 	);
 };
@@ -31,7 +36,7 @@ const RouteHarness: FC = () => {
 
 	return (
 		<>
-			<button type="button" onClick={() => navigate("/healthy")}>
+			<button onClick={() => navigate("/healthy")} type="button">
 				go healthy
 			</button>
 			<RouteErrorBoundary>
@@ -55,10 +60,10 @@ describe("RouteErrorBoundary", () => {
 	it.each(["/accounts", "/login"])(
 		"recovers a transient failure through the fallback on %s itself",
 		async (path) => {
-			authenticated = path === "/accounts";
-			let failing = true;
+			session.isAuthenticated = path === "/accounts";
+			let isFailing = true;
 			const RecoverableRoute: FC = () => {
-				if (failing) throw new Error("temporary failure");
+				if (isFailing) throw new Error("temporary failure");
 				return <div>recovered route</div>;
 			};
 			render(
@@ -71,14 +76,14 @@ describe("RouteErrorBoundary", () => {
 				</MantineProvider>,
 			);
 			const action = screen.getByRole("link", { name: "Продолжить" });
-			failing = false;
+			isFailing = false;
 			fireEvent.click(action);
 			expect(await screen.findByText("recovered route")).toBeInTheDocument();
 		},
 	);
 
 	it("keeps a persistent failure recoverable without an automatic reset loop", () => {
-		authenticated = true;
+		session.isAuthenticated = true;
 		renderBoundary("/accounts");
 		fireEvent.click(screen.getByRole("link", { name: "Продолжить" }));
 		expect(
@@ -91,7 +96,7 @@ describe("RouteErrorBoundary", () => {
 	});
 
 	it("offers document navigation when React.lazy caches a rejected chunk", async () => {
-		authenticated = false;
+		session.isAuthenticated = false;
 		const load = vi.fn(() => Promise.reject(new Error("chunk failed")));
 		const Chunk = lazy(load);
 		render(
@@ -110,18 +115,18 @@ describe("RouteErrorBoundary", () => {
 		const reload = screen.getByRole("link", { name: "Перезагрузить страницу" });
 		expect(reload).toHaveAttribute("href", "/login");
 		// Cancel browser navigation in JSDOM only after proving React Router did not intercept it.
-		let intercepted = true;
+		let isIntercepted = true;
 		const preventNavigation = (event: MouseEvent) => {
-			intercepted = event.defaultPrevented;
+			isIntercepted = event.defaultPrevented;
 			event.preventDefault();
 		};
 		document.addEventListener("click", preventNavigation, { once: true });
 		fireEvent.click(reload);
-		expect(intercepted).toBe(false);
+		expect(isIntercepted).toBe(false);
 	});
 
 	it("offers login after a public route error without error details", () => {
-		authenticated = false;
+		session.isAuthenticated = false;
 		renderBoundary("/login");
 		expect(document.title).toBe("Не удалось открыть страницу — WealthLedger");
 		expect(screen.getByRole("link", { name: "Продолжить" })).toHaveAttribute(
@@ -132,9 +137,9 @@ describe("RouteErrorBoundary", () => {
 	});
 
 	it("offers accounts after a protected route error and resets on navigation", async () => {
-		authenticated = true;
+		session.isAuthenticated = true;
 		renderBoundary("/accounts");
-		screen.getByRole("button", { name: "go healthy" }).click();
+		fireEvent.click(screen.getByRole("button", { name: "go healthy" }));
 		expect(await screen.findByText("healthy route")).toBeInTheDocument();
 	});
 });

src/app/routes/RouteErrorBoundary/RouteErrorBoundary.tsx

@@ -1,14 +1,16 @@
+import type { FC, PropsWithChildren } from "react";
+
 import { Button, Stack, Text, Title } from "@mantine/core";
 import { useDocumentTitle } from "@mantine/hooks";
-import type { FC, PropsWithChildren } from "react";
 import { Component } from "react";
 import { useTranslation } from "react-i18next";
 import { Link, useLocation } from "react-router";
+
 import { useAuth } from "@/features/auth";
 
 type BoundaryProps = PropsWithChildren<{
-	routeKey: string;
 	authenticated: boolean;
+	routeKey: string;
 }>;
 
 type RouteErrorFallbackProps = {
@@ -18,12 +20,12 @@ type RouteErrorFallbackProps = {
 type State = { hasError: boolean };
 
 class Boundary extends Component<BoundaryProps, State> {
-	state: State = { hasError: false };
-
 	static getDerivedStateFromError(): State {
 		return { hasError: true };
 	}
 
+	state: State = { hasError: false };
+
 	componentDidUpdate(previousProps: BoundaryProps) {
 		if (previousProps.routeKey !== this.props.routeKey && this.state.hasError) {
 			this.setState({ hasError: false });
@@ -31,10 +33,7 @@ class Boundary extends Component<BoundaryProps, State> {
 	}
 
 	render() {
-		if (this.state.hasError) {
-			return <RouteErrorFallback authenticated={this.props.authenticated} />;
-		}
-		return this.props.children;
+		return this.state.hasError ? <RouteErrorFallback authenticated={this.props.authenticated} /> : this.props.children;
 	}
 }
 
@@ -60,7 +59,7 @@ const RouteErrorFallback: FC<RouteErrorFallbackProps> = (props) => {
 
 const RouteErrorBoundary: FC<PropsWithChildren> = (props) => {
 	const { children } = props;
-	const { pathname, search, key } = useLocation();
+	const { key, pathname, search } = useLocation();
 	const { user } = useAuth();
 
 	return (