Add config structs with sensible defaults for tunable parameters:
- JetStreamConfig for stream retention (1 year) and replica count (1)
- HashRingConfig for virtual nodes per physical node (150)
- ShardConfig for shard count (1024) and replication factor (1)
Each component gets a new WithConfig constructor that accepts custom
configuration, while the original constructors continue to work with
defaults. Zero values in configs fall back to defaults for backward
compatibility.
Closes#38
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Test all public methods with 100% coverage:
- AddNode: updates ring, is idempotent, handles multiple nodes
- RemoveNode: updates ring, handles non-existent nodes
- GetNode: returns consistent results, handles empty ring and single node
- GetNodes and IsEmpty helper methods
Distribution tests verify:
- Balanced key distribution across nodes (< 25% deviation)
- Minimal key movement when adding nodes (< 35% moved)
- Virtual nodes improve distribution (CV < 15%)
- Ring behavior with 100+ nodes
Includes benchmarks for GetNode, AddNode, and distribution operations.
Closes#2
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
