i#93570 sw: add RES_FLTR_ANNOTATIONMARK

As commit b1cd83c625a2afeb9da43cc9745d79c01963c797 (fix crash loading
ooo#93570-3.doc, 2014-07-04) notes, the way how we map WW8 CP indexes to
sw character positions is working only in the very simple cases.

However, to do that properly, we need a way to store the start position
of an annotation mark before we create it, so add a
RES_FLTR_ANNOTATIONMARK that can do so.

Change-Id: I7cb3564621803fef9a76edaac48773cab7649ee8
i#93570 DOC import: tokenize PlcfAtnBkf and PlcfAtnBkl

So that later SwWW8ImplReader can read these structures in a way similar
to bookmarks.

Change-Id: I8e5bc804832b944336701ac12fe6cb50e17c6b94
i#93570 DOC import: handle commented text ranges via RES_FLTR_ANNOTATIONMARK

And add a minimal reproducer that shows how the old way was broken.

Change-Id: Ic2dadf9905d603b0fd0573651b235ecd5dd70e71