leg-01 reproduction

Public source retained with the related article. Generated results, dependency directories, runtime storage, secrets, and oversized binary artifacts are intentionally excluded.

README

# LEG-01 characterization boundary reproduction

This synthetic Laravel 13 fixture compares a mixed legacy postage quote with
an extracted implementation across a selected caller-visible behavior matrix.
It does not represent a Brian-owned production system.

Run the current behavior, brittle-recording, and mutation controls with:

```sh
./run.sh
```

The fixture establishes raw observations, selected characterization
assertions, public-result parity, brittle diagnostic and call-order controls,
seven behavioral mutations, two happy-path survivors, two harmless-refactor
controls, and an explicit review signal for unresolved zero-value behavior.

Structural analysis, semantic verification, source provenance, and the clean
committed-tree export are part of the drafting gate. After committing fixture
changes, verify the retained evidence with:

```sh
./bin/run-clean-export.sh HEAD
```

Retained files