* Fix download filenames to exclude CloudFront query parameters
- Strip query parameters from URLs before extracting filenames in download buttons
- Add Content-Disposition headers to CloudFront signed URLs for proper browser filename handling
* remove Download combined PDF
* we don't do multiple submissions in the iframe, so this button is not needed
* line length fix
* add fallback filename and tests
* rubocop changes
* refactor build_cloudfront_url
reduce complexity of method by extracting into other methods, also reduces need for more in line comments.
Ryan Arakawa