Add container smoke acceptance

src/guide_board/schema.py

@@ -7,6 +7,7 @@ project's own draft contracts.
 
 from __future__ import annotations
 
+import os
 from pathlib import Path
 from typing import Any
 
@@ -14,11 +15,23 @@ from guide_board.errors import ValidationError
 from guide_board.io import load_json
 
 
-SCHEMA_DIR = Path(__file__).resolve().parents[2] / "docs" / "schemas"
+SOURCE_SCHEMA_DIR = Path(__file__).resolve().parents[2] / "docs" / "schemas"
 
 
 def load_schema(schema_name: str) -> dict[str, Any]:
-    return load_json(SCHEMA_DIR / f"{schema_name}.schema.json")
+    return load_json(_schema_dir() / f"{schema_name}.schema.json")
+
+
+def _schema_dir() -> Path:
+    env_dir = os.environ.get("GUIDE_BOARD_SCHEMA_DIR")
+    candidates = []
+    if env_dir:
+        candidates.append(Path(env_dir).expanduser())
+    candidates.extend([SOURCE_SCHEMA_DIR, Path.cwd() / "docs" / "schemas"])
+    for candidate in candidates:
+        if (candidate / "target-profile.schema.json").is_file():
+            return candidate
+    return candidates[0]
 
 
 def validate_document(document: Any, schema: dict[str, Any], path: str = "$") -> list[str]: