Improve code of neo4j hook

[yangyulely]

Key Improve:

1. Added DEFAULT_NEO4J_PORT to avoid magic numbers.
2. Improved readability in get_uri by separating encryption scheme logic.
3. Changed get_client to _create_driver for clarity (private method as it's internal).
4. Kept essential logging (URI) but removed unnecessary ones.
5. Simplified session parameter handling using a conditional dictionary.
6. Used consistent line breaks and spacing for better readability.
7. Maintained type hints for better IDE support and clarity.
8. Preserved existing error handling structure while streamlining logic.

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[potiuk]

Nice!