feat: complete 3-week improvement sequence

Week 1: Code Quality Infrastructure
- Add ESLint configuration (.eslintrc.js) with modern JavaScript rules
- Add Prettier configuration (.prettierrc, .prettierignore)
- Add EditorConfig (.editorconfig) for consistent editor settings
- Update package.json scripts for linting, formatting, and quality checks
- Fix ESLint issues in existing command runners and utilities

Week 2: JavaScript/TypeScript Language Support
- Add JavaScript/TypeScript config wizard (languages/javascript/config-wizard.js)
- Add JavaScript/TypeScript tool detector (languages/javascript/tool-detector.js)
- Add JavaScript command runner (scripts/javascript/command-runner.js)
- Add 7 command files:
  - /js-setup - Interactive project configuration
  - /js-test - Run tests (Jest, Mocha, Vitest)
  - /js-lint - Run ESLint code quality checks
  - /js-build - Build JavaScript/TypeScript projects
  - /js-dev - Start development server
  - /ts-typecheck - TypeScript type checking
  - /ts-build - TypeScript compilation
- Add comprehensive documentation (commands/js-setup.md)

Week 3: Language Addition Guide
- Create LANGUAGE-ADDITION-GUIDE.md with step-by-step instructions
- Document consistent patterns for adding new languages
- Provide code templates and best practices
- Enable scalable addition of future language support

Key Improvements:
- All 62 existing tests continue to pass
- Consistent architecture across all language implementations
- Cross-platform support maintained
- Enhanced error handling with recovery suggestions
- Framework detection (React, Vue, Angular, Next.js, etc.)
- Shared utilities integration across all languages

Author: monch1962

.editorconfig

@@ -0,0 +1,31 @@
+# EditorConfig is awesome: https://EditorConfig.org
+
+# top-most EditorConfig file
+root = true
+
+[*]
+indent_style = space
+indent_size = 2
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true
+
+[*.{js,jsx,ts,tsx}]
+indent_size = 2
+
+[*.md]
+trim_trailing_whitespace = false
+max_line_length = 80
+
+[*.json]
+indent_size = 2
+
+[*.yml]
+indent_size = 2
+
+[*.sh]
+indent_size = 2
+
+[Makefile]
+indent_style = tab

.eslintrc.js

@@ -0,0 +1,81 @@
+module.exports = {
+  env: {
+    node: true,
+    es2022: true,
+  },
+  extends: ["eslint:recommended"],
+  parserOptions: {
+    ecmaVersion: "latest",
+    sourceType: "module",
+  },
+  rules: {
+    // Best practices
+    "no-console": "off", // We use console.log in CLI tools
+    "no-unused-vars": ["error", { argsIgnorePattern: "^_" }],
+    "no-var": "error",
+    "prefer-const": "error",
+
+    // Code style
+    "arrow-spacing": ["error", { before: true, after: true }],
+    "block-spacing": "error",
+    "brace-style": ["error", "1tbs", { allowSingleLine: true }],
+    "comma-dangle": ["error", "always-multiline"],
+    "comma-spacing": ["error", { before: false, after: true }],
+    "eol-last": ["error", "always"],
+    indent: ["error", 2, { SwitchCase: 1 }],
+    "key-spacing": ["error", { beforeColon: false, afterColon: true }],
+    "keyword-spacing": ["error", { before: true, after: true }],
+    "linebreak-style": ["error", "unix"],
+    "no-multiple-empty-lines": ["error", { max: 1, maxEOF: 0 }],
+    "no-trailing-spaces": "error",
+    "object-curly-spacing": ["error", "always"],
+    quotes: [
+      "error",
+      "single",
+      { avoidEscape: true, allowTemplateLiterals: true },
+    ],
+    semi: ["error", "always"],
+    "space-before-blocks": "error",
+    "space-before-function-paren": [
+      "error",
+      {
+        anonymous: "always",
+        named: "never",
+        asyncArrow: "always",
+      },
+    ],
+    "space-infix-ops": "error",
+
+    // ES6+ features
+    "arrow-parens": ["error", "always"],
+    "no-duplicate-imports": "error",
+    "prefer-arrow-callback": "error",
+    "prefer-template": "error",
+    "template-curly-spacing": ["error", "never"],
+  },
+  overrides: [
+    {
+      files: ["**/*.test.js", "**/tests/**/*.js"],
+      env: {
+        jest: true,
+      },
+      rules: {
+        "no-console": "off",
+      },
+    },
+    {
+      files: ["scripts/**/*.js", "hooks/**/*.js"],
+      rules: {
+        "no-console": "off", // CLI scripts need console output
+      },
+    },
+  ],
+  ignorePatterns: [
+    "node_modules/",
+    "dist/",
+    "build/",
+    "coverage/",
+    "*.min.js",
+    "examples/**/*",
+  ],
+};

.prettierignore

@@ -0,0 +1,10 @@
+node_modules/
+dist/
+build/
+coverage/
+*.min.js
+examples/
+package-lock.json
+yarn.lock
+pnpm-lock.yaml
+bun.lockb

.prettierrc

@@ -0,0 +1,10 @@
+{
+  "semi": true,
+  "singleQuote": true,
+  "tabWidth": 2,
+  "trailingComma": "es5",
+  "printWidth": 100,
+  "bracketSpacing": true,
+  "arrowParens": "always",
+  "endOfLine": "lf"
+}