fix(gui): Resolve AttributeError in imscope.indent and stabilize render loop

- Add 'indent' context manager to src/imgui_scopes.py.
- Refactor manual imgui.indent/unindent calls in src/gui_2.py to use imscope.indent.
- Fix cascading ImGui assertion failures caused by Open/Close mismatches during exceptions.
- Finalize 'Selectable Thinking Monologs' track.

src/imgui_scopes.py

@@ -1,4 +1,5 @@
 from __future__ import annotations
+from typing import Any
 from imgui_bundle import imgui
 from imgui_bundle import imgui_node_editor
 
@@ -43,6 +44,16 @@ class _ScopeId:
   imgui.pop_id()
   return False
 
+def indent(width: float = 0.0): return _ScopeIndent(width)
+class _ScopeIndent:
+ def __init__(self, width: float):
+  self._width = width
+ def __enter__(self):
+  imgui.indent(self._width)
+ def __exit__(self, *args):
+  imgui.unindent(self._width)
+  return False
+
 def menu(label: str): return _ScopeMenu(label)
 class _ScopeMenu:
  def __init__(self, label: str):
@@ -256,4 +267,4 @@ class _ScopeWindow:
   return self._result
  def __exit__(self, *args):
   imgui.end()
-  return False
+  return False