feat: enhance Obsidian plugin schema with HeadingRef class

surfsense_backend/tests/unit/test_obsidian_plugin_indexer.py

@@ -0,0 +1,25 @@
+from __future__ import annotations
+
+from datetime import UTC, datetime
+
+from app.schemas.obsidian_plugin import HeadingRef, NotePayload
+from app.services.obsidian_plugin_indexer import _build_metadata
+
+
+def test_build_metadata_serializes_headings_to_plain_json() -> None:
+    now = datetime.now(UTC)
+    payload = NotePayload(
+        vault_id="vault-1",
+        path="notes.md",
+        name="notes",
+        extension="md",
+        content="# Notes",
+        headings=[HeadingRef(heading="Notes", level=1)],
+        content_hash="abc123",
+        mtime=now,
+        ctime=now,
+    )
+
+    metadata = _build_metadata(payload, vault_name="My Vault", connector_id=42)
+
+    assert metadata["headings"] == [{"heading": "Notes", "level": 1}]