Enhance EspoCRM API and Webhook Handling

- Improved logging for file uploads in EspoCRMAPI to include upload parameters and error details.
- Updated cron job configurations for calendar sync and participant sync to trigger every 15 minutes on the first minute of the hour.
- Enhanced document create, delete, and update webhook handlers to determine and log the entity type.
- Refactored document sync event handler to include entity type in sync operations and logging.
- Added a new test script for uploading preview images to EspoCRM and verifying the upload process.
- Created a test script for document thumbnail generation, including document creation, file upload, webhook triggering, and preview verification.

services/espocrm.py

@@ -341,12 +341,14 @@ class EspoCRMAPI:
         form_data.add_field('role', role)
         form_data.add_field('name', filename)
         
+        self._log(f"Upload params: parentType={parent_type}, parentId={parent_id}, field={field}, role={role}")
+        
         effective_timeout = aiohttp.ClientTimeout(total=self.api_timeout_seconds)
         
         async with aiohttp.ClientSession(timeout=effective_timeout) as session:
             try:
                 async with session.post(url, headers=headers, data=form_data) as response:
-                    self._log(f"Upload response status: {response.status}", level='debug')
+                    self._log(f"Upload response status: {response.status}")
                     
                     if response.status == 401:
                         raise EspoCRMAuthError("Authentication failed - check API key")
@@ -356,6 +358,7 @@ class EspoCRMAPI:
                         raise EspoCRMError(f"Attachment endpoint not found")
                     elif response.status >= 400:
                         error_text = await response.text()
+                        self._log(f"❌ Upload failed with {response.status}. Response: {error_text}", level='error')
                         raise EspoCRMError(f"Upload error {response.status}: {error_text}")
                     
                     # Parse response