Raise Http404 rather than return HttpResponseNotFound

[SociologicalReview]

The Django docs recommend that it is better to raise the Http404 error rather than return HttpResponseNotFound so as to provide a more consistent 404 page across a website:

https://docs.djangoproject.com/en/5.2/topics/http/views/#the-http404-exception

This update replaces HttpResponseNotFound with Http404 and provides additional error handling around the parsing the of "id" parameter so as to provide a smoother experience for public visitors to a site. Additional information is given with these errors for debugging purposes.

The two lines retrieving "specific_class" and then the page itself have been replaced with a single line:

page = Page.objects.get(id=page_id).specific

in keeping with more common Wagtail practice.

The call to update "qr_code_usage" has been separated out from returning the page so as to allow a page to be returned whenever there is a valid URL, even if that specific page no longer integrates the QR code usage count.

The redirect to the page.url ends the view function to allow any other error handling to be passed onto the specific page view itself.