make sure your static resource is public...
also try putting console log and verify if this.contactList is having value in proper format.
JSON.stringify(this.contactList) should give the result as
For Aura components, you have isURLAddressable which you can implement. Example code is taken from the documentation
<aura:component implements="lightning:isUrlAddressable" description="c:helloTarget component">
<aura:attribute name="id" type="String" />
<!-- Add an "init" handler to ...
Salesforce does not guarantee all file types and their contained features will properly generate previews in Content.
Please refer this doc detailing the limitations of Content file previews.
Limitation around PDF files
Large numbers of pages. Exact number is dependent on their content but if the count is high (100+) it may cause the preview generation ...
You can access the Helptext in apex using -
String helpText = SObject.FieldAPIName__c.getDescribe().getInlineHelpText();
replace sobject name and field api name with the object and field for which you need the help text.