`error_classify::classify` maps anyhow::Error → ErrorV1 wire record by
downcasting to known typed errors (LlmError + ConfigInvalid + NotIndexed
re-exported from kebab_app::error_signal, plus std::io::Error chain).
Generic fallback emits `code: "generic"` with the chain in `details` when
verbose.
wire.rs adds wire_schema (idempotent re-tag, mirrors wire_doctor pattern
since SchemaV1 carries its own schema_version field) and wire_error_v1
(simple tag_object). Tests pin both wrappers + 7 classify code paths.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>