Clean up COM method declarations


Use IFACEMETHOD/IFACEMETHODIMP for COM methods and copy the
implementation signatures from the original declarations.

Change-Id: I71d5baacf59230f29e68f35e70144190a662160b
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
commit5ff146c9d261d04ece64941da4d68581042f9b32
parentb070f2648429a23a4846d6bb526ba6cb84a18417
authorPavel Dubsky <pavel.dubsky@qt.io>
committerPavel Dubsky <pavel.dubsky@qt.io>
commit timeMon, 23 Mar 2026 19:09:59 +0100