Implement corpus indexing and MCP search

tests/conftest.py

@@ -0,0 +1,22 @@
+from pathlib import Path
+
+import pytest
+
+from corpus_mcp.database import build_database
+
+
+@pytest.fixture
+def corpus(tmp_path: Path) -> tuple[Path, Path]:
+    source = tmp_path / "source"
+    source.mkdir()
+    (source / "guide.md").write_text(
+        "# Search Guide\n\nThe quick brown fox explains full text search.",
+        encoding="utf-8",
+    )
+    (source / "notes.txt").write_text(
+        "A second document about SQLite indexing and retrieval.",
+        encoding="utf-8",
+    )
+    database = tmp_path / "corpus.sqlite"
+    build_database(source, database, description="Test documentation")
+    return source, database