099aac87e1
Three tasks. Task 1 (#113, compile-atomic): RED-rewrite the lookup test to the six-field shape + invariant/uniqueness tests, then extend InstrumentSpec and populate the vetted table for the five instruments (refuse arm stays). Task 2 (#114, greenfield): RED the round-trip / try_from-Err / serde-bare-int / reversal tests, then add PositionAction (serde-as-i64) + PositionEvent in report.rs and re-export from the crate root. Task 3: workspace test + clippy gate. Recon-grounded line anchors; the redundant std::convert::TryFrom import dropped (2021 prelude). INDEX.md realization-note drift (C10/C15 "minimal today") deferred to the cycle-close audit, not folded here (code-only scope). refs #113 #114