Change googleDriveAdapterHelper.js to use return statement

Reverted from object literal to function with return statement

Rationale:
- User requested explicit 'return' statement for clarity
- Function wrapper with 'return' is more conventional and readable
- Makes it clear the code returns an object when executed
- Matches common module pattern expectations

Structure:
```javascript
(function() {
  // Define all classes and functions
  class DocumentCountExceededError extends Error {...}
  function generateRequestId() {...}
  // ... all other functions

  // Return object with all exports
  return {
    DocumentCountExceededError,
    generateRequestId,
    // ... all other functions
  };
})();
```

Changes:
- Wrapped entire file in IIFE: (function() { ... })()
- Changed final expression from ({ ... }) to return { ... };
- Re-added 2-space indentation for content inside function
- Updated header comment: 'Returns' → 'Function that returns'

Benefits:
✅ Explicit return statement (clearer intent)
✅ Standard IIFE module pattern
✅ More conventional JavaScript style
✅ Easier to understand for new developers
✅ Same functionality as before

Testing:
✓ Syntax validated
✓ Server starts successfully
✓ Module loads: 'Loaded global functions: googleDriveAdapterHelper'
✓ All function calls work correctly
✓ Request handling functional

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

src/globalVariables/googleDriveAdapterHelper.js

@@ -6,7 +6,7 @@
  *
  * ARCHITECTURE:
  * - Loaded by server.js using vm.Script (same as proxy.js)
- * - Returns a single object containing all helper functions
+ * - Function that returns a single object containing all helper functions
  * - Injected into globalVariableContext for access by proxy.js
  * - NO IMPORTS - All dependencies provided via VM context
  *
@@ -17,41 +17,42 @@
  * @returns {Object} Helpers object with all utility functions
  */
 
-/**
+(function() {
+  /**
    * Custom error for document count exceeding limit
    */
-class DocumentCountExceededError extends Error {
+  class DocumentCountExceededError extends Error {
-constructor(count, limit) {
+  constructor(count, limit) {
     super(`Document count ${count} exceeds limit of ${limit}`);
     this.name = "DocumentCountExceededError";
     this.count = count;
     this.limit = limit;
     this.statusCode = 413;
-}
+  }
-}
+  }
   
-// =============================================================================
+  // =============================================================================
-// Utility Functions
+  // Utility Functions
-// =============================================================================
+  // =============================================================================
   
-/**
+  /**
    * Generate a unique request ID for tracing
    * Uses UUID v4 for uniqueness
    *
    * @returns {string} Request ID in format: req_<uuid>
    */
-function generateRequestId() {
+  function generateRequestId() {
-return `req_${crypto.randomUUID()}`;
+  return `req_${crypto.randomUUID()}`;
-}
+  }
   
-/**
+  /**
    * Validate document ID format
    * Google Drive IDs are alphanumeric with hyphens and underscores
    *
    * @param {string} id - Document ID to validate
    * @returns {boolean} True if valid
    */
-function validateDocumentId(id) {
+  function validateDocumentId(id) {
     if (!id || typeof id !== "string") {
       return false;
     }
@@ -60,33 +61,33 @@ function validateDocumentId(id) {
     // Characters: a-z, A-Z, 0-9, -, _
     const pattern = /^[a-zA-Z0-9_-]{8,128}$/;
     return pattern.test(id);
-}
+  }
   
-/**
+  /**
    * Validate document count against limit
    *
    * @param {number} count - Document count
    * @param {number} limit - Maximum allowed (default: 50000)
    * @throws {DocumentCountExceededError} If count > limit
    */
-function validateDocumentCount(count, limit = 50000) {
+  function validateDocumentCount(count, limit = 50000) {
     if (count > limit) {
       throw new DocumentCountExceededError(count, limit);
     }
-}
+  }
   
-// =============================================================================
+  // =============================================================================
-// XML Utilities
+  // XML Utilities
-// =============================================================================
+  // =============================================================================
   
-/**
+  /**
    * Escape special XML characters
    * Prevents XML injection and ensures valid XML output
    *
    * @param {string} str - String to escape
    * @returns {string} Escaped string safe for XML
    */
-function escapeXml(str) {
+  function escapeXml(str) {
     if (!str) return "";
   
     return str
@@ -95,13 +96,13 @@ function escapeXml(str) {
       .replace(/>/g, "&gt;")
       .replace(/"/g, "&quot;")
       .replace(/'/g, "&apos;");
-}
+  }
   
-// =============================================================================
+  // =============================================================================
-// Error Mapping
+  // Error Mapping
-// =============================================================================
+  // =============================================================================
   
-/**
+  /**
    * Map Drive API error to HTTP status code and retry info
    *
    * Per specification:
@@ -113,7 +114,7 @@ function escapeXml(str) {
    * @param {Error} error - Drive API error
    * @returns {Object} { statusCode, retryAfter? }
    */
-function mapDriveErrorToHttp(error) {
+  function mapDriveErrorToHttp(error) {
     // Handle DocumentCountExceededError
     if (error instanceof DocumentCountExceededError) {
       return { statusCode: 413 };
@@ -146,13 +147,13 @@ function mapDriveErrorToHttp(error) {
   
     // All other errors map to 500
     return { statusCode: 500 };
-}
+  }
   
-// =============================================================================
+  // =============================================================================
-// Sitemap Functions
+  // Sitemap Functions
-// =============================================================================
+  // =============================================================================
   
-/**
+  /**
    * Transform Drive document to sitemap entry
    *
    * Creates RESTful URL in format: {baseUrl}/documents/{documentId}
@@ -164,7 +165,7 @@ function mapDriveErrorToHttp(error) {
    * @param {string} baseUrl - Base URL for the adapter
    * @returns {Object} Sitemap entry { loc, lastmod }
    */
-function toSitemapEntry(document, baseUrl) {
+  function toSitemapEntry(document, baseUrl) {
     if (!document || !document.id) {
       console.error("Invalid document for sitemap entry", { document });
       return null;
@@ -191,16 +192,16 @@ function toSitemapEntry(document, baseUrl) {
     }
   
     return { loc, lastmod };
-}
+  }
   
-/**
+  /**
    * Transform array of Drive documents to sitemap entries
    *
    * @param {Array<Object>} documents - Array of Drive API documents
    * @param {string} baseUrl - Base URL for the adapter
    * @returns {Array<Object>} Array of sitemap entries
    */
-function transformDocumentsToSitemapEntries(documents, baseUrl) {
+  function transformDocumentsToSitemapEntries(documents, baseUrl) {
     if (!Array.isArray(documents)) {
       console.error("Documents must be an array", { documents });
       return [];
@@ -209,9 +210,9 @@ function transformDocumentsToSitemapEntries(documents, baseUrl) {
     return documents
       .map((doc) => toSitemapEntry(doc, baseUrl))
       .filter((entry) => entry !== null);
-}
+  }
   
-/**
+  /**
    * Generate XML sitemap from sitemap entries
    *
    * Handles empty sitemap (0 documents) case - returns valid XML with empty urlset.
@@ -219,7 +220,7 @@ function transformDocumentsToSitemapEntries(documents, baseUrl) {
    * @param {Array<Object>} sitemapEntries - Array of { loc, lastmod } objects
    * @returns {string} Complete XML sitemap string
    */
-function generateSitemapXML(sitemapEntries) {
+  function generateSitemapXML(sitemapEntries) {
     let xml = '<?xml version="1.0" encoding="UTF-8"?>\n';
     xml += '<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">\n';
   
@@ -239,9 +240,9 @@ function generateSitemapXML(sitemapEntries) {
     xml += "</urlset>";
   
     return xml;
-}
+  }
   
-/**
+  /**
    * Main sitemap generation function
    *
    * Combines document transformation and XML generation.
@@ -250,22 +251,22 @@ function generateSitemapXML(sitemapEntries) {
    * @param {string} baseUrl - Base URL for the adapter
    * @returns {string} Complete XML sitemap
    */
-function generateSitemap(documents, baseUrl) {
+  function generateSitemap(documents, baseUrl) {
     const entries = transformDocumentsToSitemapEntries(documents, baseUrl);
     return generateSitemapXML(entries);
-}
+  }
   
-// =============================================================================
+  // =============================================================================
-// Route Parsing
+  // Route Parsing
-// =============================================================================
+  // =============================================================================
   
-/**
+  /**
    * Parse route from request
    * @param {string} method - HTTP method
    * @param {string} url - Request URL
    * @returns {Object} Route info or error
    */
-function parseRoute(method, url) {
+  function parseRoute(method, url) {
     if (method !== "GET") {
       return { route: null, error: "Method not allowed", statusCode: 405 };
     }
@@ -278,35 +279,35 @@ function parseRoute(method, url) {
       return { route: "sitemap" };
     }
   
-// All other paths return 404
+  // All other paths return 404
-return { route: null, error: "Not found", statusCode: 404 };
+  return { route: null, error: "Not found", statusCode: 404 };
-}
+  }
+  // =============================================================================
+  // Return helpers object with all functions
+  // =============================================================================
 
-// =============================================================================
+  return {
-// Return helpers object with all functions
+  // Error classes
-// =============================================================================
+  DocumentCountExceededError,
   
-({
+  // Utilities
-// Error classes
+  generateRequestId,
-DocumentCountExceededError,
+  validateDocumentId,
+  validateDocumentCount,
   
-// Utilities
+  // XML
-generateRequestId,
+  escapeXml,
-validateDocumentId,
-validateDocumentCount,
   
-// XML
+  // Error mapping
-escapeXml,
+  mapDriveErrorToHttp,
   
-// Error mapping
+  // Sitemap
-mapDriveErrorToHttp,
+  toSitemapEntry,
+  transformDocumentsToSitemapEntries,
+  generateSitemapXML,
+  generateSitemap,
   
-// Sitemap
+  // Routing
-toSitemapEntry,
+  parseRoute,
-transformDocumentsToSitemapEntries,
+  };
-generateSitemapXML,
+})();
-generateSitemap,
-
-// Routing
-parseRoute,
-});