[bug] Maestro: send-message test masks real server error with weak assertion

[vriesdemichael]

The send-message.yaml test currently passes by asserting notVisible: 'No Messages Yet'. However, screenshots show the actual result is a red error message: 'Error Loading Messages - Failed to send message'.

The test is successfully 'passing' even when the core functionality (sending a message) is failing at the backend level.

Proposed Solution:

• Update send-message.yaml to assert that the sent text is actually visible in the chat list.
• Fix the Docker test server to handled message submission or provide a proper mock response.