test(config-audit): add Opus 4.7 pattern fixtures (cache, redundant, imports, sonnet-era)

plugins/config-audit/tests/fixtures/opus-47/sonnet-era/.claude/settings.json

@@ -0,0 +1,7 @@
+{
+  "$schema": "https://json.schemastore.org/claude-code-settings.json",
+  "permissions": {
+    "allow": ["Bash(npm run *)"],
+    "deny": ["Read(./.env)"]
+  }
+}

plugins/config-audit/tests/fixtures/opus-47/sonnet-era/CLAUDE.md

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+# Sonnet-Era Clean Config
+
+## Overview
+
+Negative-control fixture for the TOK scanner. Contains no cache-breaking
+volatility, no redundant permissions, no deep import chains. Represents
+a clean, Sonnet-era configuration that pre-dates Opus 4.7 features — the
+TOK scanner should emit zero medium/high severity findings here (info
+severity is acceptable for pattern D).
+
+## Commands
+
+- `npm test`
+- `npm run build`
+
+## Conventions
+
+- TypeScript strict
+- Conventional Commits