Refactor ESLint configuration and update test rules for clarity and consistency

- Consolidated and modularized `eslint.config.mjs` with defined rules for source, test, E2E, and scripts.
- Improved test and E2E rules with relaxed settings for flexibility and enhanced mocking.
- Standardized variable naming and removed redundant imports in unit and E2E tests.
- Updated error handling and comments to align with modern TypeScript best practices (e.g., `@ts-expect-error`).

frontend/e2e/admin-access.spec.ts

@@ -7,7 +7,6 @@ import { test, expect } from '@playwright/test';
 import {
   setupAuthenticatedMocks,
   setupSuperuserMocks,
-  loginViaUI,
 } from './helpers/auth';
 
 test.describe('Admin Access Control', () => {

frontend/e2e/admin-dashboard.spec.ts

@@ -4,7 +4,7 @@
  */
 
 import { test, expect } from '@playwright/test';
-import { setupSuperuserMocks, loginViaUI } from './helpers/auth';
+import { setupSuperuserMocks } from './helpers/auth';
 
 test.describe('Admin Dashboard - Page Load', () => {
   test.beforeEach(async ({ page }) => {

frontend/e2e/admin-organization-members.spec.ts

@@ -5,7 +5,7 @@
  */
 
 import { test, expect } from '@playwright/test';
-import { setupSuperuserMocks, loginViaUI } from './helpers/auth';
+import { setupSuperuserMocks } from './helpers/auth';
 
 test.describe('Admin Organization Members - Navigation from Organizations List', () => {
   test.beforeEach(async ({ page }) => {

frontend/e2e/admin-organizations.spec.ts

@@ -4,7 +4,7 @@
  */
 
 import { test, expect } from '@playwright/test';
-import { setupSuperuserMocks, loginViaUI } from './helpers/auth';
+import { setupSuperuserMocks } from './helpers/auth';
 
 test.describe('Admin Organization Management - Page Load', () => {
   test.beforeEach(async ({ page }) => {

frontend/e2e/admin-users.spec.ts

@@ -4,7 +4,7 @@
  */
 
 import { test, expect } from '@playwright/test';
-import { setupSuperuserMocks, loginViaUI } from './helpers/auth';
+import { setupSuperuserMocks } from './helpers/auth';
 
 test.describe('Admin User Management - Page Load', () => {
   test.beforeEach(async ({ page }) => {

frontend/e2e/auth.setup.ts

@@ -11,9 +11,9 @@
  * - Savings: ~690s (~11 minutes) per test run
  */
 
-import { test as setup, expect } from '@playwright/test';
+import { test as setup } from '@playwright/test';
 import path from 'path';
-import { setupAuthenticatedMocks, setupSuperuserMocks, loginViaUI } from './helpers/auth';
+import { setupAuthenticatedMocks, setupSuperuserMocks } from './helpers/auth';
 
 // Use absolute paths to ensure correct file location
 const ADMIN_STORAGE_STATE = path.join(__dirname, '.auth', 'admin.json');

frontend/e2e/helpers/coverage.ts

@@ -57,7 +57,7 @@ export async function startCoverage(
   try {
       await page.coverage.startJSCoverage({
       resetOnNavigation: options?.resetOnNavigation ?? false,
-      // @ts-ignore
+      // @ts-expect-error - includeRawScriptCoverage is not in official types but supported by Playwright
       includeRawScriptCoverage: options?.includeRawScriptCoverage ?? false,
     });
   } catch (error) {

frontend/e2e/homepage.spec.ts

@@ -214,7 +214,7 @@ test.describe('Homepage - Mobile Menu Interactions', () => {
 
   test.skip('should close mobile menu when clicking outside', async ({ page }) => {
     // Open mobile menu
-    const mobileMenu = await openMobileMenu(page);
+    const _mobileMenu = await openMobileMenu(page);
 
     // Press Escape key to close menu (more reliable than clicking overlay)
     await page.keyboard.press('Escape');

frontend/e2e/settings-navigation.spec.ts

@@ -4,7 +4,7 @@
  */
 
 import { test, expect } from '@playwright/test';
-import { setupAuthenticatedMocks, loginViaUI } from './helpers/auth';
+import { setupAuthenticatedMocks } from './helpers/auth';
 
 test.describe('Settings Navigation', () => {
   test.beforeEach(async ({ page }) => {

frontend/e2e/settings-password.spec.ts

@@ -4,7 +4,7 @@
  */
 
 import { test, expect } from '@playwright/test';
-import { setupAuthenticatedMocks, loginViaUI } from './helpers/auth';
+import { setupAuthenticatedMocks } from './helpers/auth';
 
 test.describe('Password Change', () => {
   test.beforeEach(async ({ page }) => {

frontend/e2e/settings-profile.spec.ts

@@ -4,7 +4,7 @@
  */
 
 import { test, expect } from '@playwright/test';
-import { setupAuthenticatedMocks, loginViaUI, MOCK_USER } from './helpers/auth';
+import { setupAuthenticatedMocks, MOCK_USER } from './helpers/auth';
 
 test.describe('Profile Settings', () => {
   test.beforeEach(async ({ page }) => {