[FEATURE] Improve evaluation performance

[beeme1mr]

Overview

The flag evaluation engine in flagd leverages JsonLogic to provide a powerful and flexible rule-based serializable logic. The flagd binary and in-process Go flagd provider use this library. To improve flag evaluation performance and reduce computational overhead, the ruleset should be pre-decoded when a flag set is loaded (or updated). This removes the need to parse the JsonLogic structure for each evaluation.

Tasks

Beta Give feedback

1. Add support for pre-decoded rules in the Go JsonLogic SDK.
2. Update flagd to use the pre-decoded rules.
3. 🥇 Bonus points for running a performance test to measure the improvements

This should be a non-breaking change in the Go JsonLogic SDK.