chore: migrate ESLint config to @qlik/eslint-config@1.4.30

[Copilot]

Replaces the legacy FlatCompat/eslint-config-airbnb bridge with @qlik/eslint-config@1.4.30, a modern flat-config package from qlik-oss/dev-tools-js. Prettier is removed from the linter and should be run as a separate check.

Dependencies (package.json)

• Added: @qlik/eslint-config@1.4.30, svelte^5 (required non-optional peer dependency of @qlik/eslint-config — needed even though nebula.js does not use Svelte, because the plugin eagerly imports svelte/compiler at load time)
• Removed: eslint-config-airbnb, eslint-config-prettier, eslint-plugin-import, eslint-plugin-jsx-a11y, eslint-plugin-react, eslint-plugin-jest, eslint-plugin-prettier — all now bundled transitively or no longer needed

eslint.config.mjs rewrite

• Drops @eslint/js, @eslint/eslintrc, FlatCompat, and the compat.extends('airbnb', 'prettier') shim
• Base config switched to ...qlik.configs.react (covers JS/JSX, react, jsx-a11y, react-hooks, import-x, prettier-compat)
• Jest rules now use qlik.configs.jest[0] with an extended files glob to cover **/*.spec.js, **/*.test.js etc. (the default only targets __tests__/ directories)
• eslint-plugin-mocha block for .int/.comp files is unchanged
• All import/ rule prefixes renamed to import-x/
• import-x and react plugin instances are reused from qlik.configs.react[0].plugins to avoid duplicate-plugin conflicts
• prettier/prettier rule removed; prettier is no longer part of linting
• .eslintignore removed — content migrated to globalIgnores in eslint.config.mjs; additional ignores added for .github/**, .storybook_old/**, and **/*.d.ts

Source file changes

• Removed unused import React from 'react' from 98 JSX/JS files — the React 17+ automatic JSX transform makes the import unnecessary
• Fixed babel.config.cjs to correctly use @babel/preset-react with runtime: 'automatic', aligning Jest's Babel transform with the new JSX transform
• Added Node.js globals for CJS command files, test files, and Playwright config files
• Fixed useDeauthorizePrevOAuthInstance.js: replaced mixed require('react') call with a proper import
• Renamed stale import/ → import-x/ eslint-disable comments in source files

Rule overrides preserved

Overrides kept where @qlik/eslint-config defaults differ from this codebase's established behaviour:
no-bitwise: 0, no-plusplus: 0, no-unused-expressions: 0, react/destructuring-assignment: 0, react/prop-types: 0, react/no-deprecated: 0, import-x/no-dynamic-require: 0, no-unused-vars with caughtErrors: none.

New rules introduced by @qlik/eslint-config that are turned off for this codebase: react-hooks/exhaustive-deps, react-hooks/rules-of-hooks, React Compiler rules (react-hooks/refs, react-hooks/immutability, etc.), all testing-library/* rules, import-x/no-unresolved, import-x/extensions, and react/no-array-index-key (downgraded to warning).

[enell]

@copilot why was svelte added

[Copilot]

@qlik/eslint-config@1.4.30 bundles eslint-plugin-svelte as a dependency and lists svelte as a (non-optional) peer dependency. eslint-plugin-svelte eagerly imports svelte/compiler at module load time, so ESLint crashes with Cannot find package 'svelte' the moment @qlik/eslint-config is imported — even though nebula.js itself doesn't use Svelte. Adding svelte as a devDependency is the minimum required to satisfy that load-time import. The ideal fix is for @qlik/eslint-config to mark svelte as optional, but until that's done upstream we need it here.