feat: add recursive namespace routing and standalone runner polish

- introduce namespace-aware routing with RootParseResult, RouteResult, and InvocationContext
- register submenus as FalyxNamespace entries and resolve them through _entry_map
- refactor FalyxParser to parse only root options and leave recursive routing to Falyx
- add prepare_route, resolve_route, and route dispatch flow to Falyx
- update validator and completer to understand namespace entries and route results
- unify help/TLDR rendering APIs and add custom_tldr support on Command
- tighten Command.resolve_args error handling and parser type validation
- improve CommandRunner dependency validation and argv handling
- add BottomBar.has_items and improve wrapped executor error messages
- add tests for execution options, resolve_args, command runner, and route-aware validation

tests/test_falyx_parser/test_root_options.py

@@ -1,10 +1,8 @@
-from falyx import Falyx
 from falyx.parser.falyx_parser import FalyxParser, RootOptions
 
 
 def get_falyx_parser():
-    falyx = Falyx()
-    return FalyxParser(falyx=falyx)
+    return FalyxParser()
 
 
 def test_parse_root_options_empty():