show the tunnel end the click would actually place

The controls panel header read the type builder mode was entered with, so
tunnel mode always said Tunnel Entry even where the ghost had resolved to an
exit. Feed the header the same effective type the ghost and placement already
use.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Ne3mejABZoLWKLh8fgpM3x

src/ui/GameWorldView.cpp

@@ -1138,7 +1138,12 @@ ControlContext GameWorldView::getControlContext() const
     context.mode                   = m_buildMode.getMode();
     context.draggingBelt           = m_buildMode.isDraggingBelt();
     context.hoveredGhostIsTransfer = m_buildMode.isHoveredGhostTransfer();
-    if (m_buildMode.isBuilderMode()) { context.builderType = m_buildMode.getBuilderType(); }
+    // The type a click would actually place, so the panel agrees with the ghost when
+    // tunnel mode resolves to an exit (REQ-BLD-TUNNEL-MODE).
+    if (m_buildMode.isBuilderMode())
+    {
+        context.builderType = m_buildMode.getEffectiveBuilderType();
+    }
 
     // Buildings win over field objects, so the two are never both non-empty
     // (REQ-UI-SELECTION-CATEGORIES).