feat(api): folder_indexer.summarize_text via gpt-4o-mini

tests/test_folder_indexer.py

@@ -0,0 +1,30 @@
+"""Folder indexer LLM helpers."""
+from __future__ import annotations
+
+from unittest.mock import AsyncMock, patch
+
+import pytest
+
+from app.core.folder_indexer import summarize_text, IndexResult
+
+pytestmark = pytest.mark.asyncio
+
+
+async def test_summarize_text_returns_summary_and_tokens():
+    mock_resp = AsyncMock()
+    mock_resp.content = "Kickoff notes covering scope and deadlines."
+    mock_resp.usage_metadata = {"input_tokens": 320, "output_tokens": 18, "total_tokens": 338}
+    with patch("app.core.folder_indexer._llm_text", new=AsyncMock(return_value=mock_resp)):
+        result = await summarize_text(content="hello world", ext=".md", name="kickoff.md")
+    assert isinstance(result, IndexResult)
+    assert result.summary == "Kickoff notes covering scope and deadlines."
+    assert result.tokens_used == 338
+
+
+async def test_summarize_text_truncates_summary_at_500_chars():
+    mock_resp = AsyncMock()
+    mock_resp.content = "x" * 1000
+    mock_resp.usage_metadata = {"total_tokens": 100}
+    with patch("app.core.folder_indexer._llm_text", new=AsyncMock(return_value=mock_resp)):
+        result = await summarize_text(content="x", ext=".md", name="x.md")
+    assert len(result.summary) <= 500