fix(MultiModalModel): Lazy-load SmartPdf and guard document processing across providers; ensure SmartPdf is initialized only when needed

ts/abstract.classes.multimodal.ts

@@ -111,19 +111,30 @@ export interface ImageResponse {
 export abstract class MultiModalModel {
   /**
    * SmartPdf instance for document processing
-   * Shared across all methods that need PDF functionality
+   * Lazy-loaded only when PDF processing is needed to avoid starting browser unnecessarily
    */
-  protected smartpdfInstance: plugins.smartpdf.SmartPdf;
+  protected smartpdfInstance: plugins.smartpdf.SmartPdf | null = null;
+
+  /**
+   * Ensures SmartPdf instance is initialized and ready
+   * Call this before using smartpdfInstance in document processing methods
+   */
+  protected async ensureSmartpdfReady(): Promise<void> {
+    if (!this.smartpdfInstance) {
+      this.smartpdfInstance = new plugins.smartpdf.SmartPdf();
+      await this.smartpdfInstance.start();
+    }
+  }
 
   /**
    * Initializes the model and any necessary resources
    * Should be called before using any other methods
    */
   public async start(): Promise<void> {
-    this.smartpdfInstance = new plugins.smartpdf.SmartPdf();
-    await this.smartpdfInstance.start();
+    // SmartPdf is now lazy-loaded only when needed for PDF processing
+    // This avoids starting a browser unless document() method is actually used
   }
-  
+
   /**
    * Cleans up any resources used by the model
    * Should be called when the model is no longer needed
@@ -131,6 +142,7 @@ export abstract class MultiModalModel {
   public async stop(): Promise<void> {
     if (this.smartpdfInstance) {
       await this.smartpdfInstance.stop();
+      this.smartpdfInstance = null;
     }
   }