The system-HarfBuzz probe referenced only hb_raster_draw_create_or_fail()
and hb_raster_draw_render(), while modules/imgproc/src/drawing_text.cpp
calls ten hb_raster_* entry points. A HarfBuzz that declares the whole
hb-raster API in its header but exports only part of it passes the probe,
so OpenCV links against it instead of falling back to the bundled copy,
and the build then fails with
undefined reference to `hb_raster_draw_destroy'
Reference all ten symbols in the probe. The array is volatile because the
check compiles at -O3: a plain function address is never null, so the
compiler folds the test away and emits no relocations, which lets a
partial library pass.
Closes#29458
Avoid lossy Latin-1 conversions when creating/looking up Qt HighGUI windows and convert C-string entry points to UTF-8 explicitly. This fixes non-ASCII title handling paths that could lead to mismatched window lookup and silent display failures.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Mulham Fetna
