feature/capability-based-deps (#53)

Reviewed-on: #53
Co-authored-by: David Gwilliam <dhgwilliam@gmail.com>
Co-committed-by: David Gwilliam <dhgwilliam@gmail.com>

engine/__init__.py

@@ -1 +1,10 @@
 # engine — modular internals for mainline
+
+# Import submodules to make them accessible via engine.<name>
+# This is required for unittest.mock.patch to work with "engine.<module>.<function>"
+# strings and for direct attribute access on the engine package.
+import engine.config  # noqa: F401
+import engine.fetch  # noqa: F401
+import engine.filter  # noqa: F401
+import engine.sources  # noqa: F401
+import engine.terminal  # noqa: F401