chore: import upstream snapshot with attribution

code_review_graph/constants.py

@@ -0,0 +1,23 @@
+"""Shared constants for code-review-graph."""
+
+from __future__ import annotations
+
+import os
+
+SECURITY_KEYWORDS: frozenset[str] = frozenset({
+    "auth", "login", "password", "token", "session", "crypt", "secret",
+    "credential", "permission", "sql", "query", "execute", "connect",
+    "socket", "request", "http", "sanitize", "validate", "encrypt",
+    "decrypt", "hash", "sign", "verify", "admin", "privilege",
+})
+
+# ---------------------------------------------------------------------------
+# Configurable limits (override via environment variables)
+# ---------------------------------------------------------------------------
+MAX_IMPACT_NODES = int(os.environ.get("CRG_MAX_IMPACT_NODES", "500"))
+MAX_IMPACT_DEPTH = int(os.environ.get("CRG_MAX_IMPACT_DEPTH", "2"))
+MAX_BFS_DEPTH = int(os.environ.get("CRG_MAX_BFS_DEPTH", "15"))
+MAX_SEARCH_RESULTS = int(os.environ.get("CRG_MAX_SEARCH_RESULTS", "20"))
+
+# BFS engine: "sql" (SQLite recursive CTE) or "networkx" (Python-side BFS)
+BFS_ENGINE = os.environ.get("CRG_BFS_ENGINE", "sql")