feat(tests): scaffold + integration smoke tests (config, db, models, pipeline)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tests/scaffold/test_models.py

@@ -0,0 +1,34 @@
+"""Smoke tests for codex.models dataclasses."""
+
+from __future__ import annotations
+
+from codex.models import Chunk, Citation, CodeLink, Paper
+
+
+def test_paper_defaults() -> None:
+    """Paper(id=..., title=...) has correct optional-field defaults."""
+    p = Paper(id="2301.00001", title="T")
+    assert p.openalex_id is None
+    assert p.authors == []
+    assert p.year is None
+
+
+def test_chunk_required_fields() -> None:
+    """Chunk(paper_id=..., ord=..., content=...) has id=None and embedding=None."""
+    c = Chunk(paper_id="x", ord=0, content="c")
+    assert c.id is None
+    assert c.embedding is None
+
+
+def test_citation_fields() -> None:
+    """Citation(citing_id=..., cited_id=...) has context=None."""
+    cit = Citation(citing_id="a", cited_id="b")
+    assert cit.context is None
+
+
+def test_codelink_fields() -> None:
+    """CodeLink(symbol=...) has paper_id=None, role=None, and id=None."""
+    cl = CodeLink(symbol="foo")
+    assert cl.paper_id is None
+    assert cl.role is None
+    assert cl.id is None