feat(core): clone commands and actions when binding runtimes

Add clone support across Action types and Command so commands can be safely
registered or runner-bound without mutating the original instances.

- clone BaseAction implementations across simple, composite, IO, prompt, file,
  HTTP, process, and signal actions
- bind cloned commands in Falyx.add_command_from_command() and CommandRunner
- preserve local never_prompt settings when cloning actions
- rename shared runtime state from options to options_manager for consistency
- seed root and execution option namespaces consistently
- apply scoped root and namespace option overrides during routing and dispatch
- improve namespace completion by delegating option suggestions to FalyxParser
- enrich missing-value errors and error hints

tests/test_parsers/test_resolve_args.py

@@ -76,9 +76,10 @@ async def test_resolve_args_raises_on_conflicting_execution_option():
         )
 
     with pytest.raises(
-        CommandArgumentError, match="destination 'summary' is already defined"
+        CommandArgumentError,
+        match="destination 'summary' is already registered as an execution argument",
     ):
-        command.arg_parser.enable_execution_options(frozenset({ExecutionOption.SUMMARY}))
+        command.arg_parser._register_execution_dest("summary")
 
 
 @pytest.mark.asyncio