Add a meowlnir-whoami diagnostic script to matrix-bot-meowlnir

Asks the homeserver who Meowlnir's appservice token belongs to.
A 401 (M_UNKNOWN_TOKEN) response means the homeserver is running
without Meowlnir's appservice registration, which is the usual cause
of Meowlnir's "Failed to connect to homeserver" log messages.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

docs/configuring-playbook-bot-meowlnir.md

@@ -296,6 +296,10 @@ The playbook drives Meowlnir's management API for you based on `matrix_bot_meowl
 
 # Create another management room for an existing bot, with the given users able to command it there
 /matrix/meowlnir/bin/meowlnir-create-management-room meowlnir_bot @alice:example.com
+
+# Ask the homeserver who Meowlnir's appservice token belongs to.
+# A 401 response means the homeserver is running without Meowlnir's appservice registration, which is also what Meowlnir's own "Failed to connect to homeserver" log messages usually mean.
+/matrix/meowlnir/bin/meowlnir-whoami
 ```
 
 `meowlnir-create-management-room` prints the new room's ID, which you then register with `meowlnir-api PUT /_meowlnir/v1/management_room/<room ID>`.

roles/custom/matrix-bot-meowlnir/tasks/setup_install.yml

@@ -89,6 +89,7 @@
     - meowlnir-api
     - meowlnir-bots
     - meowlnir-create-management-room
+    - meowlnir-whoami
 
 - name: Ensure matrix-bot-meowlnir container network is created
   when: matrix_bot_meowlnir_container_network != 'host'

roles/custom/matrix-bot-meowlnir/templates/bin/meowlnir-whoami.j2

@@ -0,0 +1,31 @@
+#!/bin/sh
+# Asks the homeserver who Meowlnir's appservice token belongs to.
+#
+# A `200` response proves the homeserver has Meowlnir's appservice registration loaded.
+# A `401` (`M_UNKNOWN_TOKEN`) response means it is running without it — the condition that otherwise surfaces as Meowlnir endlessly logging "Failed to connect to homeserver".
+#
+# Usage: meowlnir-whoami
+#
+# Prints the response body, followed by the HTTP status code on its own final line.
+
+set -eu
+
+CONFIG_FILE='{{ matrix_bot_meowlnir_config_path }}/config.yaml'
+CONTAINER_NAME='matrix-bot-meowlnir'
+HOMESERVER_ADDRESS='{{ matrix_bot_meowlnir_config_homeserver_address }}'
+REQUEST_TIMEOUT='{{ matrix_bot_meowlnir_api_request_timeout_seconds }}'
+
+# The configuration file is generated by Ansible, so its layout is predictable.
+as_token="$(awk '$1 == "as_token:" { print $2; exit }' "$CONFIG_FILE" | sed 's/^"//; s/"$//')"
+
+if [ -z "$as_token" ]; then
+	echo "Could not read as_token from $CONFIG_FILE" >&2
+	exit 1
+fi
+
+# Runs curl inside the container, because the homeserver is only reachable over the container network.
+exec {{ devture_systemd_docker_base_host_command_docker }} exec "$CONTAINER_NAME" \
+	curl -sS --max-time "$REQUEST_TIMEOUT" \
+	-H "Authorization: Bearer $as_token" \
+	-w '\n%{http_code}' \
+	"$HOMESERVER_ADDRESS/_matrix/client/v3/account/whoami"

roles/custom/matrix-bot-meowlnir/templates/bin/meowlnir-whoami.j2.license

@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2026 Slavi Pantaleev
+
+SPDX-License-Identifier: AGPL-3.0-or-later