fix(#1012): invoke fallow with its real CLI and wire the report normalizer (#1044)

* fix(#1012): invoke fallow with its real CLI and wire the report normalizer

The /gsd-code-review structural pre-pass invoked fallow with flags no published
fallow version accepts (--json, --profile, --stdin-files), so it failed on every
run and degraded silently per REQ-FALLOW-02 — the feature never delivered on any
fallow version. Three compounding defects:

1. Invalid flags. Real fallow audit uses --format json (not --json), -q/--quiet,
   --changed-since/--base for changed-files scoping (no file-list input), and
   --max-crap for thresholds. There is no --profile or --stdin-files.
2. Exit-code handling. fallow audit exits 1 when it FINDS issues (verdict=fail),
   0 when clean. The pre-pass treated any non-zero exit as a crash and discarded
   the output — i.e. it threw away exactly the findings it exists to surface.
   Success is now decided by whether a valid fallow JSON report was produced,
   not by the exit code.
3. Schema mismatch. normalizeFallowReport parsed a fictional top-level schema
   (unusedExports/duplicates/circularDependencies) fallow never shipped, and was
   dead code (the workflow embedded raw JSON; its tests asserted the fictional
   schema, one even calling a non-existent runFallowAudit and passing vacuously).

Fixes: align the invocation to fallow's documented agent-facing pattern; map the
profile preset (minimal/standard/strict) to --max-crap (50/30/15); scope phase
runs via --changed-since with a repo-scope fallback; rewrite the normalizer to
fallow's real schema (dead_code.unused_exports/unused_files/circular_dependencies
+ duplication.clone_groups) and wire it into the workflow so the reviewer
receives normalized findings; replace the fictional-schema fixtures and tests
with real-schema ones and delete the vacuous runFallowAudit test.

Closes #1012

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* chore(#1012): backfill changeset PR number to 1044

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

---------

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

docs/CONFIGURATION.md

@@ -292,7 +292,7 @@ The `code_quality.*` namespace gates optional structural-analysis tooling that a
 |---------|------|---------|-------------|
 | `code_quality.fallow.enabled` | boolean | `false` | Enables fallow structural pre-pass for `/gsd-code-review`. When `false`, no fallow binary probe or JSON artifact is produced. |
 | `code_quality.fallow.scope` | string | `phase` | Scope for fallow analysis: `phase` (current review file scope) or `repo` (entire repository). |
-| `code_quality.fallow.profile` | string | `standard` | Fallow profile selector passed to the pre-pass runner (`minimal`, `standard`, `strict`). |
+| `code_quality.fallow.profile` | string | `standard` | Strictness preset for the fallow pre-pass (`minimal`, `standard`, `strict`). Fallow has no native profile concept, so this maps to its `--max-crap` complexity threshold: `minimal`→50, `standard`→30, `strict`→15 (lower = stricter). |
 | `code_quality.fallow.mcp` | boolean | `false` | **Reserved — not yet implemented.** When `true`, enables MCP-backed structural findings mode for runtimes that support MCP server routing. Setting this to `true` is currently a no-op and emits a runtime warning. |
 
 ## Ship Settings