release: v0.2.0 (version bump + CHANGELOG)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: adrida

CHANGELOG.md

@@ -0,0 +1,49 @@
+# Changelog
+
+All notable changes to TRACER are recorded here. This project follows semantic
+versioning.
+
+## 0.2.0 (2026-06)
+
+### Added
+- `tracer scan`: a fast, conservative day-one read of a traces file, before any
+  training. It groups traffic by similarity and measures, on a held-out slice it
+  never saw, how much a near-free model can answer at your target agreement,
+  using exact Clopper-Pearson bounds, with an optional per-1k and monthly savings
+  estimate. Ships a self-contained HTML report with an interactive 3D map of the
+  embedding space (hover-to-inspect cells, a Verdict/Label colour toggle, and
+  PCA/UMAP/t-SNE layouts). Exposed as `tracer.scan()`.
+- Distance-based OOD safety gate: at inference the router defers inputs that fall
+  far from the training distribution (kNN distance, global and per-predicted-label
+  thresholds) regardless of surrogate confidence, so off-distribution traffic goes
+  to the teacher instead of getting a confident guess.
+- `tracer fit --trees` to opt in the tree surrogates, and `--skip` to drop named
+  candidates from the zoo.
+- Trace loaders accept common key aliases for both input and label
+  (`input/query/text/prompt/question` and
+  `teacher/teacher_output/label/intent/output/answer`).
+- Bring-your-own embeddings for `tracer scan`: local sentence-transformers by
+  default (`--embed-model`), a precomputed `.npy` (`--embeddings`), or your own
+  HTTP embedding endpoint (`--embed-url`, with header and response-key options).
+
+### Changed
+- The parity gate now certifies on an exact held-out lower bound instead of an
+  in-sample point estimate, so a policy cannot clear the target by in-sample luck
+  and then break the contract on real traffic. Coverage is now monotonic in the
+  target, and a hybrid select-then-verify procedure recovers coverage at strict
+  targets that a plain held-out split discarded.
+- Tree surrogates (decision tree, random forest, extra-trees, gradient boosting)
+  are now off by default in `tracer fit`; the default zoo is the fast linear and
+  MLP heads. Use `--trees` for hard, high-class-count tasks.
+- The HTML report is restyled to the light Tracer theme, and the word "audit" is
+  dropped across the report and docs.
+
+### Fixed
+- Non-monotonic coverage in the gate (a stricter target could deploy more coverage
+  than a looser one).
+- NaN-robustness in acceptor fitting on degenerate surrogates.
+
+## 0.1.3
+
+Initial public releases: the parity-gated router (`fit`, `update`, `load_router`,
+`serve`), the HTML report and Sankey diagram, and the embedder factories.

src/tracer/__init__.py

@@ -23,7 +23,7 @@
     TraceRecord,
 )
 
-__version__ = "0.1.3"
+__version__ = "0.2.0"
 
 __all__ = [
     # Core API