feat(server): custom library scanning interval (#4390)

* 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

---------

Co-authored-by: Jason Rasmussen <jrasm91@gmail.com>

server/src/domain/system-config/system-config.service.spec.ts

@@ -121,6 +121,12 @@ const updatedConfig = Object.freeze<SystemConfig>({
   theme: {
     customCss: '',
   },
+  library: {
+    scan: {
+      enabled: true,
+      cronExpression: '0 0 * * *',
+    },
+  },
 });
 
 describe(SystemConfigService.name, () => {