task(config): Add circuit breaker configuration support

[currantw]

Description

Add ClientCircuitBreakerConfiguration to the client configuration, matching the existing implementation in Java, Python, Node, and Go (valkey-io/valkey-glide#6050). The circuit breaker logic lives in the Rust core, this task only requires adding the config class, serializing it to protobuf, and surfacing the CircuitBreakerException type to callers.

Checklist

• Add ClientCircuitBreakerConfiguration class with builder/options pattern
• Serialize config to protobuf ConnectionRequest
• Add CircuitBreakerException type
• Add unit test for config serialization

Related

• Core, Java, Python, Node, Go: Add client-wide circuit breaker valkey-glide#6050
• Add client-wide circuit breaker valkey-glide#5996

Additional Information

⚪ None