Manage notification channels separately and migrate

It's more convenient to manage notification channels separately, as it
is done with email settings. Notification hook and other forms are
adopted to only select channels. Hooks can now use more than one
channel.

modules/webapp/src/main/elm/Messages/Page/UserSettings.elm

@@ -15,6 +15,7 @@ import Messages.Comp.ChangePasswordForm
 import Messages.Comp.DueItemsTaskManage
 import Messages.Comp.EmailSettingsManage
 import Messages.Comp.ImapSettingsManage
+import Messages.Comp.NotificationChannelManage
 import Messages.Comp.NotificationHookManage
 import Messages.Comp.OtpSetup
 import Messages.Comp.PeriodicQueryTaskManage
@@ -31,6 +32,7 @@ type alias Texts =
     , scanMailboxManage : Messages.Comp.ScanMailboxManage.Texts
     , notificationHookManage : Messages.Comp.NotificationHookManage.Texts
     , periodicQueryTask : Messages.Comp.PeriodicQueryTaskManage.Texts
+    , channelManage : Messages.Comp.NotificationChannelManage.Texts
     , otpSetup : Messages.Comp.OtpSetup.Texts
     , userSettings : String
     , uiSettings : String
@@ -38,6 +40,7 @@ type alias Texts =
     , scanMailbox : String
     , emailSettingSmtp : String
     , emailSettingImap : String
+    , channelSettings : String
     , changePassword : String
     , uiSettingsInfo : String
     , scanMailboxInfo1 : String
@@ -50,6 +53,8 @@ type alias Texts =
     , webhookInfoText : String
     , dueItemsInfoText : String
     , periodicQueryInfoText : String
+    , channels : String
+    , channelInfoText : String
     }
 
 
@@ -63,6 +68,7 @@ gb =
     , scanMailboxManage = Messages.Comp.ScanMailboxManage.gb
     , notificationHookManage = Messages.Comp.NotificationHookManage.gb
     , periodicQueryTask = Messages.Comp.PeriodicQueryTaskManage.gb
+    , channelManage = Messages.Comp.NotificationChannelManage.gb
     , otpSetup = Messages.Comp.OtpSetup.gb
     , userSettings = "User Settings"
     , uiSettings = "UI Settings"
@@ -71,6 +77,7 @@ gb =
     , emailSettingSmtp = "E-Mail Settings (SMTP)"
     , emailSettingImap = "E-Mail Settings (IMAP)"
     , changePassword = "Change Password"
+    , channelSettings = "Notification Channels"
     , uiSettingsInfo =
         "These settings only affect the web ui. They are stored in the browser, "
             ++ "so they are separated between browsers and devices."
@@ -103,14 +110,16 @@ its payload.
 Additionally, you can setup queries that are executed periodically.
 The results are send as a notification message.
 
-When creating a new notification task, choose first the communication
-channel.
+A notification setting needs at least one communication channel, which
+must be created before.
 
 """
     , webhookInfoText = """Webhooks execute http request upon certain events in docspell.
 """
     , dueItemsInfoText = """Docspell can notify you once the due dates of your items come closer.  """
     , periodicQueryInfoText = "You can define a custom query that gets executed periodically."
+    , channels = "Notification Channels"
+    , channelInfoText = "Channels are used to send notification messages."
     }
 
 
@@ -124,6 +133,7 @@ de =
     , scanMailboxManage = Messages.Comp.ScanMailboxManage.de
     , notificationHookManage = Messages.Comp.NotificationHookManage.de
     , periodicQueryTask = Messages.Comp.PeriodicQueryTaskManage.de
+    , channelManage = Messages.Comp.NotificationChannelManage.de
     , otpSetup = Messages.Comp.OtpSetup.de
     , userSettings = "Benutzereinstellung"
     , uiSettings = "Oberfläche"
@@ -131,6 +141,7 @@ de =
     , scanMailbox = "E-Mail-Import"
     , emailSettingSmtp = "E-Mail-Einstellungen (SMTP)"
     , emailSettingImap = "E-Mail-Einstellungen (IMAP)"
+    , channelSettings = "Benachrichtigungskanäle"
     , changePassword = "Passwort ändern"
     , uiSettingsInfo =
         "Diese Einstellungen sind für die Web-Oberfläche."
@@ -161,15 +172,16 @@ Es kann aus diesen Versandkanälen gewählt werden:
 E-Mail. Zusätzlich kann das HTTP request direkt empfangen werden, was
 alle Details zu einem Ereignis enthält.
 
-
 Ausserdem können periodische Suchabfragen erstellt werden, dessen
 Ergebnis dann als Benachrichtigung versendet wird.
 
-Beim Erstellen eines neuen Auftrags muss zunächst der gewünschte
-Versandkanal gewählt werden.
+Für eine Notifikation ist ein Kommunikationskanal notwendig, der zuvor
+erstellt werden muss.
 
 """
     , webhookInfoText = """Webhooks versenden HTTP Requests wenn bestimmte Ereignisse in Docspell auftreten."""
     , dueItemsInfoText = """Docspell kann dich benachrichtigen, sobald das Fälligkeitsdatum von Dokumenten näher kommt. """
     , periodicQueryInfoText = "Hier können beliebige Abfragen definiert werden, welche regelmäßig ausgeführt werden."
+    , channels = "Benachrichtigungskanäle"
+    , channelInfoText = "Über Kanäle werden Notifizierungen versendet."
     }