Improve URL encoding in createFile() Location field

Background

The Location field returned by createFile() in index.js currently uses raw params.Key without URL encoding. This is pre-existing behavior that should be improved to properly handle filenames with special characters (e.g., spaces, parentheses).

Problem

Filenames with spaces or special characters (e.g., my file (1).txt) produce technically malformed URLs in the Location field:

• Current: https://bucket.s3.region.amazonaws.com/my file (1).txt
• Expected: https://bucket.s3.region.amazonaws.com/my%20file%20(1).txt

Solution

Apply proper URL encoding to params.Key when constructing the Location URL, using:

params.Key.split('/').map(encodeURIComponent).join('/')

This matches the logic already used in getFileLocation() and avoids encoding path separators.

References

• PR #459
• Comment: https://github.com/parse-community/parse-server-s3-adapter/pull/459#discussion_r2835761821
• Identified by: @mtrezza