* add automatic library scan config options
* add validation
* open api
* use CronJob instead of cron-validator
* fix tests
* catch potential error of the library scan initialization
* better description for input field
* move library scan job initialization to server app service
* fix tests
* add comments to all parameters of cronjob contructor
* make scan a child of a more general library object
* open api
* chore: cleanup
* move cronjob handling to job repoistory
* web: select for common cron expressions
* fix open api
* fix tests
* put scanning settings in nested accordion
* fix system config validation
* refactor, tests
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Co-authored-by: Jason Rasmussen <jrasm91@gmail.com>