Fix ImportError: Import up module instead of function

Changed the import in commands/__init__.py from importing the up
function to importing the up module. This fixes the AttributeError
where cli.py was trying to access up.run but up was a function
instead of a module.

Fixes the error:
AttributeError: 'function' object has no attribute 'run'

Author: claude

src/devman/commands/__init__.py

@@ -6,7 +6,7 @@
 from . import index
 from .init import init
 from .switch import switch
-from .up import up
+from . import up
 
 __all__ = [
     "bootstrap",