[V5] openbb-core: Add Backwards-Compatible Layered Config System (openbb.toml) (#7492)

* add backwards-compatible layered config system

* fix path reference in windows test

* need python version-aware handling in docstring generator

Author: deeleeramone

openbb_platform/core/openbb_core/app/config/__init__.py

@@ -0,0 +1,27 @@
+"""Layered configuration discovery for openbb-core.
+
+Mirrors the resolution order ``openbb-cli`` ships with — pyproject →
+user-global → project → explicit → .env → real-shell env vars — and
+maps the merged result onto the existing ``SystemService`` and
+``UserService`` singletons. New code should import from this
+subpackage; the legacy ``user_settings.json`` / ``system_settings.json``
+disk files keep working unchanged as one layer in the cascade.
+"""
+
+from openbb_core.app.config.loader import (
+    apply_config_to_services,
+    apply_settings_to_env,
+    load_config,
+    load_env_files,
+    load_layered_config,
+    render_config_template,
+)
+
+__all__ = [
+    "apply_config_to_services",
+    "apply_settings_to_env",
+    "load_config",
+    "load_env_files",
+    "load_layered_config",
+    "render_config_template",
+]