Implement the GOON (Graph Object Output Notation) format encoder in the knowledge-graph Rust service and wire it through the Rails integration. ## What GOON is an LLM-optimized text format for knowledge graph query results. It transforms `GraphResponse` (nodes + edges) into a token-efficient format with progressive disclosure and navigation hints, built on top of TOON encoding. ## Key deliverables - Rewrite ADR 005 and format spec to reflect TOON-based design - Implement `GoonFormatter` in Rust (currently a 24-line stub) - Wire `format=llm` through REST API (`POST /api/v4/orbit/query`) - Add snapshot tests per query type (search, traversal, neighbors, path finding, aggregation) - Update `query_graph` tool description with GOON format guide ## References - [GOON / API Design ADR (snippet)](https://gitlab.com/gitlab-org/gitlab/-/snippets/4929205) - [TOON Specification](https://github.com/toon-format/spec/blob/main/SPEC.md) - Branch: `arivera/goon-format-adr` - [Claude research session](https://claude.ai/chat/4a1d3f0b-2a23-45c9-a3b3-2250815bbe34)