[Help wanted][Enhancement] Refactor condition matchers

[hezean]

https://github.com/FeatureProbe/server-sdk-java/blob/8c71ba45767b6de96171a4e426dbfa21addf9b4d/src/main/java/com/featureprobe/sdk/server/model/Condition.java#L25-L33

using map for predicate matching isn't a good practice, consider using strategy pattern or so.