feat: add dark source inspection interface

tests/test_health.py

@@ -12,8 +12,18 @@ def test_health_returns_healthy() -> None:
     assert response.json() == {"status": "healthy"}
 
 
-def test_root_identifies_application() -> None:
+def test_root_renders_interface() -> None:
     response = client.get("/")
 
     assert response.status_code == 200
-    assert response.json() == {"name": "Media Ingest", "status": "running"}
+    assert response.headers["content-type"].startswith("text/html")
+    assert "Media Ingest" in response.text
+    assert 'id="inspect-form"' in response.text
+    assert 'id="new-source"' in response.text
+
+
+def test_static_styles_are_served() -> None:
+    response = client.get("/static/styles.css")
+
+    assert response.status_code == 200
+    assert "--background" in response.text