The bridge subscribed to <root>/#, so the broker sent back every discover_r, alexaResponce and changeReport
the bridge published, and the backend's <endpointId>/alexaDirective_e. It now subscribes to <root>/discover
and <root>/+/alexaDirective, both named in src/topics.ts; a directive topic is recognised by the root and the
last segment instead of by counting three segments.
The test reads the subscriptions from the broker, publishes seven other topics under the root and one
directive for each of two endpoints: the bridge receives the two directives and the discovery request,
nothing else. Tests: 148 -> 150 (the count in the body of 6789a1a, 108 -> 113, should read 143 -> 148).
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>