If I close a file, project or Geany, it would be nice, next time I work on a project, and open previously used files, to remember the positions in file and scroll the view directly there. This would save time to re-scroll each time I reopen the file. Another scenario is in case of a power failure - so I can remember were I left (This of course would work with a feature to also remember/restore opened files whenever a new project is opened).
Geany should already do most of what you ask, if preference General->"Load files from last session" is set on close it will remember what files are open and restore them at the same place next time (unless you explicitly tell it not to with the -s option)
For the projects to do the same, preference General->"Use project-based session files" does the same thing, after you close the project next time you open the project it will open the same files at the same places.
Switching projects should switch the sets of open files.
If you close Geany with a project open it will re-open it next time you start Geany.
However Geany must be shutdown normally to be able to save this information, on power failure, or shutdown or logout Geany is just killed and does not have time to save the session, so it should restart at the previous session.
@Lex - I don't believe that addresses the OP's feature request.
What I'm looking for is simply remembering the line:column position in the recent files, and placing the cursor there when re-opening a file, instead of at 1:1.
Currently, if you scroll down in a file, close it, and immediately open it again, the cursor will be reset to 1:1.