khive-vcs-adapters 0.2.6

KG import/export format adapters (ADR-036).

Adapters are pure transforms in the two-stage pipeline:

source file
    | adapter (pure transform — no DB access)
intermediate NDJSON (entities + edges, in-memory or temp file)
    | khive kg import (validates + loads)
working.db

P0 (shipped): [FormatAdapter] trait, [EntityRecord], [EdgeRecord], and the [AdapterError] type.

P1 (deferred): BibTeX, Turtle/N-Triples, JSON-LD adapters. P2 (deferred): GraphML, GEXF, Markdown adapters.