Move cutscene mode to renderer

This patch splits "cutscene mode" (disabling silhouttes, territory
borders and other visual overlays) from the cinema manager component
and moves it to the renderer, since it doesn't influence the simulation
anyway. The mode can now be independently controlled by the GUI. This
is done so it can also be used for other narrative elements like speech
or dialogue in the future. Cutscene mode is still always enabled while
cinema paths are playing, though.
By design, this also fixes the issue that range overlays weren't hidden
during cutscene mode.

source/renderer/RenderingOptions.cpp

@@ -1,4 +1,4 @@
-/* Copyright (C) 2025 Wildfire Games.
+/* Copyright (C) 2026 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -138,6 +138,7 @@ CRenderingOptions::CRenderingOptions() : m_ConfigHooks(new ConfigHooks())
 	m_DisplayFrustum = false;
 	m_DisplayShadowsFrustum = false;
 	m_RenderActors = true;
+	m_CutsceneMode = false;
 }
 
 CRenderingOptions::~CRenderingOptions()