E2BE not working for mautrix bridges

Fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/806

roles/matrix-bridge-mautrix-signal/defaults/main.yml

@@ -43,6 +43,8 @@ matrix_mautrix_signal_daemon_systemd_wanted_services_list: []
 matrix_mautrix_signal_appservice_token: ''
 matrix_mautrix_signal_homeserver_token: ''
 
+matrix_mautrix_signal_appservice_bot_username: signalbot
+
 # Database-related configuration fields
 #
 # This bridge only supports postgres.

roles/matrix-bridge-mautrix-signal/templates/config.yaml.j2

@@ -43,7 +43,7 @@ appservice:
     # The unique ID of this appservice.
     id: signal
     # Username of the appservice bot.
-    bot_username: signalbot
+    bot_username: {{ matrix_mautrix_signal_appservice_bot_username|to_json }}
     # Display name and avatar for bot. Set to "remove" to remove display name/avatar, leave empty
     # to leave display name/avatar as-is.
     bot_displayname: Signal bridge bot

roles/matrix-bridge-mautrix-signal/templates/registration.yaml.j2

@@ -6,9 +6,12 @@ namespaces:
     users:
     - exclusive: true
       regex: '^@signal_.+:{{ matrix_mautrix_signal_homeserver_domain|regex_escape }}$'
+    - exclusive: true
+      regex: '^@{{ matrix_mautrix_signal_appservice_bot_username|regex_escape }}:{{ matrix_mautrix_signal_homeserver_domain|regex_escape }}$'
     aliases:
     - exclusive: true
       regex: '^#signal_.+:{{ matrix_mautrix_signal_homeserver_domain|regex_escape }}$'
 url: {{ matrix_mautrix_signal_appservice_address }}
-sender_localpart: signalbot
+# See https://github.com/tulir/mautrix-signal/issues/43
+sender_localpart: _bot_{{ matrix_mautrix_signal_appservice_bot_username|to_json }}
 rate_limited: false