MLE-24763 Upgrading from jshint to eslint

No linting fixes yet. Changing from the older jshint to the modern eslint. The eslint config doesn't enforce whitespace yet, will do that in a later PR.

Author: rjrudin

.jshintrc

@@ -0,0 +1,67 @@
+// ESLint 9+ flat config
+const globals = require("globals");
+
+module.exports = [
+  {
+    // Base configuration for all JS files
+    files: ["**/*.js"],
+    languageOptions: {
+      ecmaVersion: 2022,
+      sourceType: "commonjs", // Node.js uses CommonJS
+      globals: {
+        ...globals.commonjs,
+        ...globals.node,
+        ...globals.browser,  // Add browser globals like setTimeout
+        structuredClone: "readonly",
+        // Legacy globals from old config
+        Atomics: "readonly",
+        SharedArrayBuffer: "readonly"
+      }
+    },
+    rules: {
+      // Spacing and formatting
+      "indent": "off", // TODO: Fix indentation in separate PR
+      "linebreak-style": ["error", "unix"],
+      "quotes": ["error", "single"],
+      "semi": ["error", "always"],
+
+      // Modern best practices
+      "eqeqeq": "error",
+      "curly": ["error", "all"], // Require braces for all control structures
+      "no-unused-vars": "error",
+      "no-undef": "error",
+
+      // Spacing rules (disabled for initial setup - TODO: Fix in separate PR)
+      "arrow-spacing": "off",
+      "space-before-blocks": "off",
+      "space-before-function-paren": "off",
+      "space-in-parens": "off",
+      "object-curly-spacing": "off",
+      "keyword-spacing": "off",
+      "comma-spacing": "off",
+      "key-spacing": "off",
+      "space-infix-ops": "off",
+
+      // Style rules (disabled for initial setup - TODO: Fix in separate PR)
+      "array-bracket-spacing": "off",
+      "block-spacing": "off",
+      "brace-style": "off",
+      "func-call-spacing": "off",
+      "no-trailing-spaces": "off",
+
+      // Disable console errors for this project
+      "no-console": "off",
+
+      // Bracket notation preference
+      "dot-notation": "error"
+    }
+  },
+  {
+    // Ignore patterns
+    ignores: [
+      "**/data/*.js",
+      "node_modules/**",
+      "coverage/**"
+    ]
+  }
+];

eslint.config.js

@@ -3,7 +3,7 @@
 */
 const path   = require('path');
 const gulp   = require('gulp');
-const jshint = require('gulp-jshint');
+const eslint = require('gulp-eslint-new');
 const mocha  = require('gulp-mocha');
 const jsdoc  = require('gulp-jsdoc3');
 
@@ -17,9 +17,10 @@ const basicloader = require('./lib/basic-loader.js');
 const streamToArray = require("stream-to-array");
 
 function lint() {
-  return gulp.src('lib/*')
-      .pipe(jshint({lookup:true}))
-      .pipe(jshint.reporter('default'));
+  return gulp.src('lib/*.js')
+      .pipe(eslint({ overrideConfigFile: 'eslint.config.js' }))
+      .pipe(eslint.format())
+      .pipe(eslint.failAfterError());
 }
 
 function test() {