New "user-preferences-tracking-topics" plugin outlet (#30821)

Adds the "user-preferences-tracking-topics" plugin outlet to allow the
`discourse-assign` plugin to add a new "notification level when
assigned" user preference.

There's also a new `customAttrNames` tracked property that allows
plugins to add new user option to be saved from this screen / plugin
outlet.

Also changed the text used for the "notification level when replying" to
match the one that is used for the "notification level when assigned" in
https://github.com/discourse/discourse-assign/pull/626.

## BEFORE

<img width="375" alt="image"
src="https://github.com/user-attachments/assets/178ba47e-f783-46d2-adae-28afec49b259"
/>

## AFTER

<img width="363" alt="Screenshot 2025-01-16 at 16 11 26"
src="https://github.com/user-attachments/assets/215e9f86-62f7-48ea-b665-72cbf28abd21"
/>

DEV: remove unused topic-tracking component

app/assets/javascripts/discourse/app/components/user-preferences/topic-tracking.hbs

@@ -1,36 +0,0 @@
-<div class="user-preferences_tracking-topics-controls">
-  <div class="controls controls-dropdown">
-    <label>{{i18n "user.new_topic_duration.label"}}</label>
-    <ComboBox
-      @valueProperty="value"
-      @content={{@considerNewTopicOptions}}
-      @value={{@model.user_option.new_topic_duration_minutes}}
-      @onChange={{fn (mut @model.user_option.new_topic_duration_minutes)}}
-      class="duration"
-    />
-  </div>
-
-  <div class="controls controls-dropdown">
-    <label>{{i18n "user.auto_track_topics"}}</label>
-    <ComboBox
-      @valueProperty="value"
-      @content={{@autoTrackDurations}}
-      @value={{@model.user_option.auto_track_topics_after_msecs}}
-      @onChange={{action
-        (mut @model.user_option.auto_track_topics_after_msecs)
-      }}
-    />
-  </div>
-
-  <div class="controls controls-dropdown">
-    <label>{{i18n "user.notification_level_when_replying"}}</label>
-    <ComboBox
-      @valueProperty="value"
-      @content={{@notificationLevelsForReplying}}
-      @value={{@model.user_option.notification_level_when_replying}}
-      @onChange={{action
-        (mut @model.user_option.notification_level_when_replying)
-      }}
-    />
-  </div>
-</div>

app/assets/javascripts/discourse/app/controllers/preferences/tracking.js

@@ -10,6 +10,7 @@ export default class extends Controller {
   @service currentUser;
   @service siteSettings;
   @tracked saved = false;
+  @tracked customAttrNames = [];
 
   likeNotificationFrequencies = [
     { name: i18n("user.like_notification_frequency.always"), value: 0 },
@@ -53,15 +54,15 @@ export default class extends Controller {
 
   notificationLevelsForReplying = [
     {
-      name: i18n("topic.notifications.watching.title"),
+      name: i18n("user.notification_level_when_replying.watch_topic"),
       value: NotificationLevels.WATCHING,
     },
     {
-      name: i18n("topic.notifications.tracking.title"),
+      name: i18n("user.notification_level_when_replying.track_topic"),
       value: NotificationLevels.TRACKING,
     },
     {
-      name: i18n("topic.notifications.regular.title"),
+      name: i18n("user.notification_level_when_replying.do_nothing"),
       value: NotificationLevels.REGULAR,
     },
   ];
@@ -154,7 +155,8 @@ export default class extends Controller {
 
   @computed(
     "siteSettings.tagging_enabled",
-    "siteSettings.mute_all_categories_by_default"
+    "siteSettings.mute_all_categories_by_default",
+    "customAttrNames"
   )
   get saveAttrNames() {
     const attrs = [
@@ -180,6 +182,10 @@ export default class extends Controller {
       );
     }
 
+    if (this.customAttrNames?.length > 0) {
+      attrs.push(...this.customAttrNames);
+    }
+
     return attrs;
   }
 
@@ -189,9 +195,7 @@ export default class extends Controller {
 
     return this.model
       .save(this.saveAttrNames)
-      .then(() => {
-        this.saved = true;
-      })
+      .then(() => (this.saved = true))
       .catch(popupAjaxError);
   }
 }

app/assets/javascripts/discourse/app/templates/preferences/tracking.hbs

@@ -39,7 +39,7 @@
       class="controls controls-dropdown"
       data-setting-name="user-notification-level-when-replying"
     >
-      <label>{{i18n "user.notification_level_when_replying"}}</label>
+      <label>{{i18n "user.notification_level_when_replying.label"}}</label>
       <ComboBox
         @valueProperty="value"
         @content={{this.notificationLevelsForReplying}}
@@ -50,6 +50,11 @@
       />
     </div>
 
+    <PluginOutlet
+      @name="user-preferences-tracking-topics"
+      @outletArgs={{hash model=this.model customAttrNames=this.customAttrNames}}
+    />
+
     <PreferenceCheckbox
       @labelKey="user.topics_unread_when_closed"
       @checked={{this.model.user_option.topics_unread_when_closed}}

config/locales/client.en.yml

@@ -1925,7 +1925,11 @@ en:
         after_5_minutes: "after 5 minutes"
         after_10_minutes: "after 10 minutes"
 
-      notification_level_when_replying: "When I post in a topic, set that topic to"
+      notification_level_when_replying: 
+        label: "When posting"
+        watch_topic: "Watch topic"
+        track_topic: "Track topic"
+        do_nothing: "Do nothing"
       topics_unread_when_closed: "Consider topics unread when they are closed"
 
       invited: