feat(aggregate): support dictionary-based file entries with optional tiers

tests/test_tiered_context.py

@@ -66,3 +66,44 @@ def test_build_tier3_context_exists():
     # Let's check for the header
     assert "other.py" in result
     assert "AST Skeleton" in result
+
+def test_build_file_items_with_tiers(tmp_path):
+    from aggregate import build_file_items
+    
+    # Create some dummy files
+    file1 = tmp_path / "file1.txt"
+    file1.write_text("content1")
+    file2 = tmp_path / "file2.txt"
+    file2.write_text("content2")
+    
+    files_config = [
+        "file1.txt",
+        {"path": "file2.txt", "tier": 3}
+    ]
+    
+    items = build_file_items(tmp_path, files_config)
+    
+    assert len(items) == 2
+    
+    item1 = next(i for i in items if i["entry"] == "file1.txt")
+    assert item1["content"] == "content1"
+    assert "tier" in item1
+    assert item1["tier"] is None
+    
+    item2 = next(i for i in items if i["entry"] == "file2.txt")
+    assert item2["content"] == "content2"
+    assert item2["tier"] == 3
+
+def test_build_files_section_with_dicts(tmp_path):
+    from aggregate import build_files_section
+    
+    file1 = tmp_path / "file1.txt"
+    file1.write_text("content1")
+    
+    files_config = [
+        {"path": str(file1)}
+    ]
+    
+    result = build_files_section(tmp_path, files_config)
+    assert "content1" in result
+    assert "file1.txt" in result