MAESTRO: stabilize coverage runs and fix tests

backend/app/engine/analyzer.py

@@ -16,7 +16,7 @@ from .models import (
 from .parser import HeaderParser, ParsedHeader
 from .scanner_base import BaseScanner
 from .scanner_registry import ScannerRegistry
-from .scanners._legacy_adapter import configure_legacy
+from .scanners._legacy_adapter import configure_legacy, reset_legacy_context
 
 ProgressCallback = Callable[[int, int, str], None]
 
@@ -42,6 +42,7 @@ class HeaderAnalyzer:
         progress_callback: ProgressCallback | None = None,
     ) -> AnalysisResult:
         start = perf_counter()
+        reset_legacy_context()
         configure_legacy(
             resolve=request.config.resolve,
             decode_all=request.config.decode_all,

backend/app/engine/scanners/_legacy_adapter.py

@@ -33,6 +33,13 @@ def configure_legacy(
     _LEGACY_CONFIG["include_unusual"] = bool(include_unusual)
 
 
+def reset_legacy_context() -> None:
+    global _CONTEXT_SIGNATURE, _CONTEXT_CONFIG, _CONTEXT_ANALYSIS
+    _CONTEXT_SIGNATURE = None
+    _CONTEXT_CONFIG = None
+    _CONTEXT_ANALYSIS = None
+
+
 def _load_legacy_module() -> object:
     global _LEGACY_MODULE
     if _LEGACY_MODULE is not None:

backend/pyproject.toml

@@ -18,6 +18,7 @@ dependencies = [
 dev = [
   "pytest>=8.0",
   "pytest-asyncio>=0.23",
+  "pytest-cov>=5.0",
   "httpx>=0.27",
   "ruff>=0.4",
 ]