feat: enforce @/ alias for imports and fix all relative parent imports (#16787)

## Summary
This PR enforces the use of `@/` alias for imports instead of relative
parent imports (`../`).

## Changes

### ESLint Configuration
- Added `no-restricted-imports` pattern in `eslint.config.react.mjs` to
block `../*` imports with the message "Relative parent imports are not
allowed. Use @/ alias instead."
- Removed the non-working `import/no-relative-parent-imports` rule
(doesn't work properly in ESLint flat config)

### VS Code Settings
- Added `javascript.preferences.importModuleSpecifier: non-relative` to
`.vscode/settings.json` (TypeScript setting was already there)

### Code Fixes
- Fixed **941 relative parent imports** across **706 files** in
`packages/twenty-front`
- All `../` imports converted to use `@/` alias

## Why
- Consistent import style across the codebase
- Easier to move files without breaking imports
- Better IDE support for auto-imports
- Clearer understanding of where imports come from

packages/twenty-front/src/modules/command-menu/components/CommandMenuWidthEffect.tsx

@@ -4,7 +4,7 @@ import { useRecoilValue } from 'recoil';
 import {
   COMMAND_MENU_WIDTH_VAR,
   commandMenuWidthState,
-} from '../states/commandMenuWidthState';
+} from '@/command-menu/states/commandMenuWidthState';
 
 export const CommandMenuWidthEffect = () => {
   const commandMenuWidth = useRecoilValue(commandMenuWidthState);

packages/twenty-front/src/modules/command-menu/components/__stories__/CommandMenu.stories.tsx

@@ -32,7 +32,7 @@ import { HttpResponse, graphql } from 'msw';
 import { IconDotsVertical } from 'twenty-ui/display';
 import { I18nFrontDecorator } from '~/testing/decorators/I18nFrontDecorator';
 import { JestContextStoreSetter } from '~/testing/jest/JestContextStoreSetter';
-import { type CommandMenu } from '../CommandMenu';
+import { type CommandMenu } from '@/command-menu/components/CommandMenu';
 
 const openTimeout = 50;