[bugfix] media.Processor{}.GetFile() returning 404s on first call, correctly loading on 2nd (#3129)

* refactor file handling a tiny bit

* whoops

* make processing media / emoji defers a bit clear to see that it's the "on finished processing" path

* some wording

* add some debug logging

* add mutex locks for processing remote media

* try removing freshness check

* fix derefMedia not being allocated

* fix log format string

* handle case of empty file paths (i.e. not stored)

* remove media / emoji once finished processing from dereferencer maps

* whoops, fix the cached / force checks

* move url parsing outside of 'process___Safely()' funcs to prevalidate url

* use emoji.ShortcodeDomain()

* update RefreshEmoji() to also match RefreshMedia() changes

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Co-authored-by: tobi <tobi.smethurst@protonmail.com>

internal/cleaner/media.go

@@ -97,7 +97,7 @@ func (m *Media) PruneOrphaned(ctx context.Context) (int, error) {
 	if err := m.state.Storage.WalkKeys(ctx, func(path string) error {
 		// Check for our expected fileserver path format.
 		if !regexes.FilePath.MatchString(path) {
-			log.Warn(ctx, "unexpected storage item: %s", path)
+			log.Warnf(ctx, "unexpected storage item: %s", path)
 			return nil
 		}