Improve backwards configshell-fb compatibility

Basically copying what has been done in rtslib_fb.py.
This allows correct importing of submodules.

configshell_fb.py

@@ -1,12 +1,21 @@
-# Providing backwards compatibility for modules importing 'configshell_fb'
-
-from configshell import ConfigNode, ConfigShell, Console, ExecutionError, Log, Prefs
-
-__all__ = [
-    'Console',
-    'Log',
-    'ConfigNode',
-    'ExecutionError',
-    'Prefs',
-    'ConfigShell',
-]
+"""
+configshell_fb.py - Backwards compatibility module for configshell
+
+This module provides backwards compatibility for code that imports 'configshell_fb'.
+It re-exports all public names from the 'configshell' module.
+
+Usage:
+    from configshell_fb import ConfigNode, Log, Console  # etc.
+
+Note: This compatibility layer may be deprecated in future versions.
+Please consider updating your imports to use 'configshell' directly.
+"""
+
+import configshell
+from configshell import *  # noqa: F403
+
+# Explicitly import and re-export submodules
+from configshell import console, log, node, prefs, shell  # noqa: F401
+
+# Re-export all public names from configshell
+__all__ = configshell.__all__