Trac ticket number

ticket-27929

Branch description

When collecting static files with ManifestStaticFilesStorage, both hashed and original versions are created by default. This adds a keep_original_files attribute to allow removal of original non-hashed files after processing for production deployments where only hashed versions are needed.

There have already been two PR's on this #17328 by @theumang100 and #16625 by @valleyofblackpanther
This PR is more inspired by whitenoise's approach of keeping a track of which files to delete during processing and then deleting them at the end, though uses a slightly different approach.

It also makes it more convenient to update the ManifestStaticFilesStorage configuration from the already supported OPTIONS keyword of the STORAGES setting.
eg

{
    "default": {
        "BACKEND": "django.core.files.storage.FileSystemStorage",
    },
    "staticfiles": {
        "BACKEND": "django.contrib.staticfiles.storage.ManifestStaticFilesStorage",
        "OPTIONS":  {
            "keep_original_files": False,
            "manifest_name": "secured_through_obscurity_staticfiles.json",
            "manifest_strict": False,
            "support_js_module_import_aggregation": True,
        },
    },
}

Checklist

• This PR targets the main branch.
• The commit message is written in past tense, mentions the ticket number, and ends with a period.
• I have checked the "Has patch" ticket flag in the Trac system.
• I have added or updated relevant tests.
• I have added or updated relevant docs, including release notes if applicable.
• I have attached screenshots in both light and dark modes for any UI changes.