LPR improvements (#16559)

* use a small yolov9 model for detection

* use yolov9 for users without frigate+ and update retention algorithm

* new lpr config fields

* levenshtein distance package

* tweaks

* docs

docker/main/requirements-wheels.txt

@@ -53,6 +53,7 @@ pywebpush == 2.0.*
 # alpr
 pyclipper == 1.3.*
 shapely == 2.0.*
+Levenshtein==0.26.*
 prometheus-client == 0.21.*
 # HailoRT Wheels
 appdirs==1.4.*