Handle no neo4j case gracefully

[snakajima]

Summary by CodeRabbit

• Enhancement: Improved the get_graph_history function to handle situations when the Neo4j driver is not initialized correctly. This change increases the reliability of the function and provides more informative responses.
• New Feature: Added a "neo4j" status indicator to the JSON response of the get_graph_history function. This feature provides users with immediate feedback on the status of the Neo4j driver, enhancing the transparency of the system's operation.

[coderabbitai[bot]]

Walkthrough

The get_graph_history function in main.py has been enhanced to handle the case when the Neo4j driver is not initialized correctly. It now includes a new key "neo4j" in the JSON response to indicate the driver's status, improving error handling and response clarity.

Changes

File	Summary
main.py	The get_graph_history function now checks if the Neo4j driver is initialized and returns an appropriate response. A new key "neo4j" is added to the JSON response to indicate the driver's status. This change improves error handling and provides more information in the response.

🐇

"In the land of code, where logic intertwines,

A rabbit hops, leaving bugs behind.

With each key press, a new world unfurls,

In the realm of brackets, where the Neo4j whirls.

Now clearer responses, our function sends,

A tale of success, that never ends." 🎉

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