Vendor helgoboss/helgobox (ReaLearn) as basis for custom UI fork

Stripped upstream git history; starting point for replacing the native
SWELL/Win32 mapping UI with something more suited to bulk editing.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

plugin-reaper-realearn/doc/helgobox/modules/ROOT/pages/app/user-interface/title-bar.adoc

@@ -0,0 +1,55 @@
+= Title bar
+
+The bar on the top of the app window is the _Title bar_.
+It primarily provides general functions, such as window controls, access to settings, and quick access to the REAPER transport.
+
+image::generated/screenshots/elements/area/window-title-bar-0.png[]
+
+include::partial$generated/elements/title-bar/close-window.adoc[]
+
+This has the same effect as pressing xref:helgobox::plug-in/user-interface/menu-bar.adoc#close-app[].
+
+include::partial$generated/elements/title-bar/full-screen.adoc[]
+
+include::partial$generated/elements/title-bar/move-window.adoc[]
+
+include::partial$generated/elements/title-bar/toggle-nav-bar.adoc[]
+
+include::partial$generated/elements/title-bar/theme-mode.adoc[]
+
+include::partial$generated/elements/title-bar/dim.adoc[]
+
+The opacity of the opaque window can be adjusted via xref:app/user-interface/settings-dialog.adoc#settings-dim-opacity[].
+
+include::partial$generated/elements/title-bar/settings.adoc[]
+
+See xref:app/user-interface/settings-dialog.adoc[].
+
+include::partial$generated/elements/title-bar/refresh.adoc[]
+
+include::partial$generated/elements/title-bar/undo.adoc[]
+
+include::partial$generated/elements/title-bar/redo.adoc[]
+
+include::partial$generated/elements/title-bar/theme-switcher.adoc[]
+
+Themes are simply pre-selected combinations of various appearance settings.
+Once you’ve selected a theme, you can further customize it by adjusting the settings.
+
+include::partial$generated/elements/title-bar/panic-midi.adoc[]
+
+include::partial$generated/elements/title-bar/save-project.adoc[]
+
+include::partial$generated/elements/title-bar/play-arrangement.adoc[]
+
+include::partial$generated/elements/title-bar/stop-arrangement.adoc[]
+
+include::partial$generated/elements/title-bar/pause-arrangement.adoc[]
+
+include::partial$generated/elements/title-bar/help.adoc[]
+
+See xref:app/user-interface/help-menu.adoc[].
+
+include::partial$generated/elements/title-bar/helgobox-info.adoc[]
+
+See xref:key-concepts.adoc#instance-id[].