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_falyx/test_options_manager_contract.py

@@ -0,0 +1,219 @@
+import pytest
+
+from falyx import Falyx
+from falyx.action import Action, ChainedAction
+from falyx.command import Command
+from falyx.options_manager import OptionsManager
+
+
+def test_seed_missing_and_override_namespace_do_not_leak():
+    options = OptionsManager()
+    options.set("verbose", True, "root")
+
+    options.seed_missing({"verbose": False, "debug_hooks": False}, "root")
+    assert options.get("verbose", namespace_name="root") is True
+    assert options.get("debug_hooks", namespace_name="root") is False
+
+    with options.override_namespace({"verbose": False}, "root"):
+        assert options.get("verbose", namespace_name="root") is False
+
+    assert options.get("verbose", namespace_name="root") is True
+
+
+def test_command_and_action_read_options_from_expected_namespace():
+    options = OptionsManager()
+    options.from_mapping({"region": "us-east"}, "default")
+    options.from_mapping({"never_prompt": True, "verbose": True}, "root")
+
+    action = Action("deploy-action", lambda: "ok")
+    command = Command.build(
+        key="D",
+        description="Deploy",
+        action=action,
+        options_manager=options,
+    )
+
+    command._inject_options_manager()
+
+    assert command.get_option("region") == "us-east"
+    assert command.get_option("verbose", namespace_name="root") is True
+
+    assert action.get_option("region") == "us-east"
+    assert action.get_option("verbose", namespace_name="root") is True
+    assert action.never_prompt is True
+    assert action.local_never_prompt is None
+
+
+def test_all_objects_in_one_namespace_share_same_options_manager():
+    flx = Falyx(program="root")
+
+    chain = ChainedAction(
+        name="deploy-flow",
+        actions=[
+            Action("step-one", lambda: "one"),
+            Action("step-two", lambda: "two"),
+        ],
+    )
+    command = flx.add_command("D", "Deploy", action=chain)
+
+    command._inject_options_manager()
+
+    assert flx._executor.options_manager is flx.options_manager
+    assert flx.exit_command.options_manager is flx.options_manager
+    assert flx.help_command.options_manager is flx.options_manager
+
+    if flx.history_command:
+        assert flx.history_command.options_manager is flx.options_manager
+        assert flx.history_command.arg_parser.options_manager is flx.options_manager
+
+    for builtin in flx.builtins.values():
+        assert builtin.options_manager is flx.options_manager
+        if builtin.arg_parser:
+            assert builtin.arg_parser.options_manager is flx.options_manager
+
+    assert command.options_manager is flx.options_manager
+    assert command.arg_parser.options_manager is flx.options_manager
+
+    assert chain.options_manager is flx.options_manager
+    for child_action in chain.actions:
+        assert child_action.options_manager is flx.options_manager
+
+
+def test_nested_namespace_may_keep_distinct_options_manager_if_intended():
+    root_options = OptionsManager()
+    child_options = OptionsManager()
+
+    root = Falyx(program="root", options_manager=root_options)
+    child = Falyx(program="child", options_manager=child_options)
+    child_command = child.add_command("D", "Deploy", action=lambda: "ok")
+
+    root.add_submenu(
+        key="C",
+        description="Child Menu",
+        submenu=child,
+    )
+
+    assert root.options_manager is root_options
+    assert child.options_manager is child_options
+    assert root.options_manager is not child.options_manager
+
+    assert root._executor.options_manager is root_options
+    assert child._executor.options_manager is child_options
+
+    assert child_command.options_manager is child_options
+    assert child_command.arg_parser.options_manager is child_options
+
+    assert child.exit_command.options_manager is child_options
+    assert child.help_command.options_manager is child_options
+    if child.history_command:
+        assert child.history_command.options_manager is child_options
+
+    assert root.namespaces["C"].namespace is child
+
+
+@pytest.mark.asyncio
+async def test_nested_namespace_receives_temporary_root_overrides_during_routed_execution():
+    root_options = OptionsManager()
+    child_options = OptionsManager()
+
+    root = Falyx(program="root", options_manager=root_options)
+    child = Falyx(program="child", options_manager=child_options)
+    child.add_command("D", "Deploy", action=lambda: "ok", aliases=["deploy"])
+
+    child.options_manager.set("verbose", False, "root")
+
+    root.add_submenu(
+        key="C",
+        description="Child Menu",
+        submenu=child,
+    )
+
+    seen_during_dispatch = {}
+
+    async def fake_dispatch_route(*, route, args, kwargs, execution_args, **_):
+        assert route.namespace is child
+        seen_during_dispatch["verbose"] = route.namespace.options_manager.get(
+            "verbose", False, "root"
+        )
+        assert seen_during_dispatch["verbose"] is True
+        return "ok"
+
+    root._dispatch_route = fake_dispatch_route
+
+    result = await root.execute_command("--verbose C D")
+
+    assert result == "ok"
+    assert seen_during_dispatch["verbose"] is True
+
+    result = await root.execute_command("C --verbose D")
+
+    assert result == "ok"
+    assert seen_during_dispatch["verbose"] is True
+
+    assert child.options_manager is child_options
+    assert child.options_manager.get("verbose", False, "root") is False
+    assert root.options_manager is root_options
+
+
+@pytest.mark.asyncio
+async def test_execute_command_applies_root_defaults_without_overwriting_existing_root_values():
+    child = Falyx(program="child")
+    child.add_command("D", "Deploy", action=lambda: "ok", aliases=["deploy"])
+
+    child.options_manager.set("verbose", True, "root")
+
+    root = Falyx(program="root")
+    root.add_submenu(
+        key="C",
+        description="Child Menu",
+        submenu=child,
+    )
+
+    async def fake_dispatch_route(*, route, args, kwargs, execution_args, **_):
+        assert route.namespace is child
+        assert route.root_overrides == {}
+        assert route.root_defaults["verbose"] is False
+        assert route.namespace.options_manager.get("verbose", False, "root") is True
+        return "ok"
+
+    root._dispatch_route = fake_dispatch_route
+
+    result = await root.execute_command("C D")
+
+    assert result == "ok"
+    assert child.options_manager.get("verbose", False, "root") is True
+
+
+@pytest.mark.asyncio
+async def test_execute_command_applies_root_overrides_temporarily_and_restores_root_namespace():
+    child = Falyx(program="child")
+    child.add_command("D", "Deploy", action=lambda: "ok", aliases=["deploy"])
+
+    child.options_manager.set("verbose", False, "root")
+
+    root = Falyx(program="root")
+    root.add_submenu(
+        key="C",
+        description="Child Menu",
+        submenu=child,
+    )
+
+    seen_during_dispatch = {}
+
+    async def fake_dispatch_route(*, route, args, kwargs, execution_args, **_):
+        assert route.namespace is child
+        assert route.root_overrides == {"verbose": True}
+        seen_during_dispatch["verbose"] = route.namespace.options_manager.get(
+            "verbose", False, "root"
+        )
+        assert seen_during_dispatch["verbose"] is True
+        return "ok"
+
+    root._dispatch_route = fake_dispatch_route
+
+    result = await root.execute_command("--verbose C D")
+
+    assert result == "ok"
+    assert seen_during_dispatch["verbose"] is True
+
+    assert child.options_manager.get("verbose", False, "root") is False