Create an endpoint to list available tokens

[ShayestehHS]

We need an endpoint that lists the currently available tokens. The application is configured to always have 4 ready-to-use tokens. However, there might be instances where fewer than 4 tokens are available.

The endpoint should perform the following actions:

1. Retrieve the available ready-to-use tokens.
2. If fewer than 4 tokens are available, generate the remaining tokens to ensure there are always 4 tokens available.
3. Return the list of available tokens after ensuring the count is up to 4.

Acceptance Criteria:

1. Create an endpoint to list available tokens.
2. The endpoint should first retrieve the ready-to-use tokens from the database.
3. If there are fewer than 4 tokens available:
   • Generate the remaining tokens to ensure a total of 4 tokens.
   • Save the newly generated tokens to the database.
4. Return a list of 4 available tokens.

Additional Notes:

• Ensure that the token generation logic adheres to existing validation rules.
• Handle any potential errors in the token retrieval or generation process.