fix: notify new mail again when a push names Email but not EmailDelivery #34

On main every push ran the mail task, whose legacy path notifies the
newest unread inbox mail. Device sync narrowed that to pushes naming
EmailDelivery, so contact and calendar changes never notify. But a
subscription made by an older build listens to Email and Mailbox until
the app is opened again, and a server without EmailDelivery reports
new mail only as those changes. Their new mail no longer showed a
notification while the app was closed.

Email and Mailbox now count as possible mail again, in the native push
router and in the push task alike. A push that names only contact or
calendar types still never takes the mail path.

Checked with the push router and push task tests: an Email or Mailbox
change starts the task and the legacy path notifies the message,
next to the syncs a mixed map asks for.

android/app/src/main/java/com/anonymous/bulwarkmobile/sync/PushRouting.kt

@@ -13,7 +13,7 @@ import org.json.JSONObject
  * The relay forwards the JMAP StateChange's `changed` map verbatim (FCM data
  * key `changed`: JMAP account id → type → state; only its first account is
  * repeated as `accountId`), so every account key is looked at. The mail task
- * runs only for mail: when some account's map has `EmailDelivery`, for an
+ * runs only for mail: when some account's map has a mail type, for an
  * EmailPush, or when `changed` is missing or unreadable (older relays), so a
  * contact change never ends in a mail notification.
  */
@@ -28,7 +28,15 @@ object PushRouting {
     )
 
     private const val EMAIL_PUSH_KIND = "jmap-email-push"
-    private const val EMAIL_DELIVERY = "EmailDelivery"
+
+    /**
+     * Types that may mean new mail: `EmailDelivery`, and `Email`/`Mailbox`,
+     * which new mail changes too. A subscription made by an older build
+     * listens to them until the launch-time resync replaces its types, and a
+     * server without `EmailDelivery` has only them. Keep in sync with
+     * MAIL_TYPES in src/lib/push-background-task.ts.
+     */
+    private val MAIL_TYPES = setOf("EmailDelivery", "Email", "Mailbox")
     private val CONTACT_TYPES = setOf("ContactCard", "AddressBook")
     private val CALENDAR_TYPES = setOf("CalendarEvent", "Calendar")
 
@@ -42,7 +50,7 @@ object PushRouting {
                 mail = true
                 continue
             }
-            if (EMAIL_DELIVERY in types) mail = true
+            if (types.any { it in MAIL_TYPES }) mail = true
             val contacts = types.any { it in CONTACT_TYPES }
             val calendar = types.any { it in CALENDAR_TYPES }
             for (route in routes[jmapAccountId].orEmpty()) {