password reset fails

@rsc: When trying to do a password reset via forgot PW dialog in the GUI, the plugin fails with these error messages:

Dec 22, 2023 12:35:05 PM systems.dmx.signup.SignupPlugin requestInitiatePasswordReset
SEVERE: null
java.lang.RuntimeException: There seems to be an issue with your mail (SMTP) setup, we FAILED sending out the 'password reset' mail
	at systems.dmx.signup.SignupPlugin.sendPasswordResetMail(SignupPlugin.java:883)
	at systems.dmx.signup.SignupPlugin.sendPasswordResetToken(SignupPlugin.java:763)
	at systems.dmx.signup.SignupPlugin.requestInitiatePasswordReset(SignupPlugin.java:367)
	at systems.dmx.signup_ui.usecase.InitiatePasswordResetWithNameUseCase.invoke(InitiatePasswordResetWithNameUseCase.java:28)
	at systems.dmx.signup_ui.SignupUiPlugin.initiatePasswordResetWithName(SignupUiPlugin.java:174)
	at systems.dmx.signup_ui.SignupUiPlugin.initiatePasswordReset(SignupUiPlugin.java:155)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at com.sun.jersey.spi.container.JavaMethodInvokerFactory$1.invoke(JavaMethodInvokerFactory.java:60)
	at com.sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$ResponseOutInvoker._dispatch(AbstractResourceMethodDispatchProvider.java:205)
	at com.sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.java:75)
	at com.sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.java:302)
	at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:147)
	at com.sun.jersey.server.impl.uri.rules.ResourceObjectRule.accept(ResourceObjectRule.java:100)
	at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:147)
	at com.sun.jersey.server.impl.uri.rules.RootResourceClassesRule.accept(RootResourceClassesRule.java:84)
	at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1480)
	at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1411)
	at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1360)
	at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1350)
	at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:416)
	at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:538)
	at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:716)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
	at org.apache.felix.http.base.internal.handler.ServletHandler.doHandle(ServletHandler.java:339)
	at org.apache.felix.http.base.internal.handler.ServletHandler.handle(ServletHandler.java:300)
	at org.apache.felix.http.base.internal.dispatch.ServletPipeline.handle(ServletPipeline.java:93)
	at org.apache.felix.http.base.internal.dispatch.InvocationFilterChain.doFilter(InvocationFilterChain.java:50)
	at org.apache.felix.http.base.internal.dispatch.HttpFilterChain.doFilter(HttpFilterChain.java:31)
	at org.apache.felix.http.base.internal.dispatch.FilterPipeline.dispatch(FilterPipeline.java:76)
	at org.apache.felix.http.base.internal.dispatch.Dispatcher.dispatch(Dispatcher.java:49)
	at org.apache.felix.http.base.internal.DispatcherServlet.service(DispatcherServlet.java:67)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
	at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:684)
	at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:501)
	at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:229)
	at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1086)
	at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:428)
	at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:193)
	at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1020)
	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:135)
	at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:255)
	at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:116)
	at org.eclipse.jetty.server.Server.handle(Server.java:370)
	at org.eclipse.jetty.server.AbstractHttpConnection.handleRequest(AbstractHttpConnection.java:494)
	at org.eclipse.jetty.server.AbstractHttpConnection.headerComplete(AbstractHttpConnection.java:971)
	at org.eclipse.jetty.server.AbstractHttpConnection$RequestHandler.headerComplete(AbstractHttpConnection.java:1033)
	at org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:644)
	at org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:235)
	at org.eclipse.jetty.server.AsyncHttpConnection.handle(AsyncHttpConnection.java:82)
	at org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle(SelectChannelEndPoint.java:667)
	at org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run(SelectChannelEndPoint.java:52)
	at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:608)
	at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:543)
	at java.lang.Thread.run(Thread.java:748)
Caused by: java.util.MissingResourceException: Can't find resource for bundle java.util.PropertyResourceBundle, key mail_signature
	at java.util.ResourceBundle.getObject(ResourceBundle.java:450)
	at java.util.ResourceBundle.getString(ResourceBundle.java:407)
	at systems.dmx.signup_ui.email.SignUpUiEmailTextProducer.getPasswordResetMailMessage(SignUpUiEmailTextProducer.java:109)
	at systems.dmx.signup.SignupPlugin.sendPasswordResetMail(SignupPlugin.java:880)
	... 56 more

AC: When no extra language ressource files are provided via the file system (config dir), a fallback to the existing ressources (within the bundle) should be the default. At least an English fallback should be provided. In any case the service should not fail. AC: It should be possible to overwrite existing or add extra language files for missing languages via the file system.