Loads and deep-merges config.json with credentials.json at startup.
Delegates to a pluggable loader (default = the production ConfigLoader-
backed factory exported by ./Config/ConfigLoaderFactory.js) so tests
can swap the implementation without touching the public surface.
Loads and deep-merges config.json with credentials.json at startup.
Delegates to a pluggable loader (default = the production ConfigLoader- backed factory exported by
./Config/ConfigLoaderFactory.js) so tests can swap the implementation without touching the public surface.