[Feature] - Securely Store and Manage `api_key` on PicoBricks

[RespectMathias]

Description

Implement secure storage and management of the api_key on the PicoBricks board to authenticate with the WiFi2BLE REST API.

Motivation

To protect sensitive information and prevent unauthorized access to the desk control system via the API.

Proposed Solution

• Store the api_key securely on the PicoBricks board.
• Restrict exposure of the api_key within the code.
• Ensure the api_key is not printed to the console or included in logs.
• Test scenarios where the api_key is missing or incorrect to ensure proper error handling.

Acceptance Criteria

• Feature is clearly defined
• Meets proposed solution
• Tests considered

Additional Info

Consider encrypting the api_key if time permits. Ensure compliance with best practices for embedded device security.