[BUG]: Filtering on event data with language like summary is not possible

Describe the bug
A clear and concise description of what the bug is.

To Reproduce
Steps to reproduce the behavior:
Use for example this calendar:
https://abfuhrtermine.awp-paf.de/WasteManagementPfaffenhofen/WasteManagementServiceServlet?ApplicationName=Calendar&SubmitAction=sync&StandortID=165472001&AboID=284378&Fra=RM;B;P;S

It contains for example SUMMARY;LANGUAGE=de:Restmuell or DESCRIPTION;LANGUAGE=de:Bitte stellen Sie die Behälter bis 6:00 Uhr zur Abholung bereit..

If you configure the filterProperty to "summary", the summary attribute contains an object like:

{
 "params": {
  "LANGUAGE": "de"
 },
 "val": "Restmuell "
}

This is the reason why the regex filter can not work, it is no string, it is an object.

Expected behavior
If the property is an object and contains a key "val", use this attribute for filtering.

kalender-events/src/lib.ts

Lines 438 to 446 in e186020

    
           if (Array.isArray(filterProperty)) { 
        
               for (const prop of filterProperty) { 
        
                   if (regex.test(prop)) { 
        
                       return true; 
        
                   } 
        
               } 
        
           } else { 
        
               return regex.test(filterProperty); 
        
           }

can be changed to something like:

            if (Array.isArray(filterProperty)) {
                for (const prop of filterProperty) {
                    if (regex.test(prop)) {
                        return true;
                    }
                }
            } else if (typeof filterProperty === 'object' && 'val' in filterProperty) {
                return regex.test(filterProperty.val);
            } else {
                return regex.test(filterProperty);
            }

This code is not tested, but should work.

The issue was found while using node-red-contrib-ical-events.

Fixed with v0.28.1

	if (Array.isArray(filterProperty)) {
	for (const prop of filterProperty) {
	if (regex.test(prop)) {
	return true;
	}
	}
	} else {
	return regex.test(filterProperty);
	}