[performance] media processing improvements (#1288)

* media processor consolidation and reformatting, reduce amount of required syscalls

Signed-off-by: kim <grufwub@gmail.com>

* update go-store library, stream jpeg/png encoding + use buffer pools, improved media processing AlreadyExists error handling

Signed-off-by: kim <grufwub@gmail.com>

* fix duration not being set, fix mp4 test expecting error

Signed-off-by: kim <grufwub@gmail.com>

* fix test expecting media files with different extension

Signed-off-by: kim <grufwub@gmail.com>

* remove unused code

Signed-off-by: kim <grufwub@gmail.com>

* fix expected storage paths in tests, update expected test thumbnails

Signed-off-by: kim <grufwub@gmail.com>

* remove dead code

Signed-off-by: kim <grufwub@gmail.com>

* fix cached presigned s3 url fetching

Signed-off-by: kim <grufwub@gmail.com>

* fix tests

Signed-off-by: kim <grufwub@gmail.com>

* fix test models

Signed-off-by: kim <grufwub@gmail.com>

* update media processing to use sync.Once{} for concurrency protection

Signed-off-by: kim <grufwub@gmail.com>

* shutup linter

Signed-off-by: kim <grufwub@gmail.com>

* fix passing in KVStore GetStream() as stream to PutStream()

Signed-off-by: kim <grufwub@gmail.com>

* fix unlocks of storage keys

Signed-off-by: kim <grufwub@gmail.com>

* whoops, return the error...

Signed-off-by: kim <grufwub@gmail.com>

* pour one out for tobi's code <3

Signed-off-by: kim <grufwub@gmail.com>

* add back the byte slurping code

Signed-off-by: kim <grufwub@gmail.com>

* check for both ErrUnexpectedEOF and EOF

Signed-off-by: kim <grufwub@gmail.com>

* add back links to file format header information

Signed-off-by: kim <grufwub@gmail.com>

Signed-off-by: kim <grufwub@gmail.com>

vendor/codeberg.org/gruf/go-mutexes/map.go

@@ -454,7 +454,9 @@ func (mu *rwmutex) Unlock() {
 	if mu.rcnt > 0 {
 		// RUnlock
 		mu.rcnt--
-	} else {
+	}
+
+	if mu.rcnt == 0 {
 		// Total unlock
 		mu.lock = 0
 	}