Add LiveStream class for managing live queries

[jonathanrbarney]

What is the motivation?

To Add support for Live Query result fetching

Type of Change

• 📚 Examples / docs / tutorials / dependencies update
• 🔧 Bug fix (non-breaking change which fixes an issue)
• 🥂 Improvement (non-breaking change which improves an existing feature)
• 🚀 New feature (non-breaking change which adds functionality)
• 💥 Breaking change (fix or feature that would cause existing functionality to change)
• 🔐 Security fix

What does this change do?

This change implements initial support for live queries and listening to the result stream rather than simply returning the live query ID as the SDK currently does.

Note that the limitation of one live query per Surreal class instance and associated required connection state changes is a result of the current implementation choice to use the connection in a blocking way with _send_receive. Multiplexing of multiple live query streams is possible with custom listener handling routing for received messages and use of callbacks but represents a fundamental change to the way this SDK currently operates which is why I chose not to implement it.

Is this related to any issues?

#34

Have you read the Contributing Guidelines?

• I have read the Contributing Guidelines