Add a filter (e.g. by Status) to the Global Gantt view, same as the Projects list

[joacoetche06]

Context: we need to filter the Global Gantt the same way the Projects list can already be filtered (see screenshot of the search builder with a "Characteristics - Status" filter).

Current behavior: the Global Gantt shows every project/task open with no filtering at all, which makes it hard to read once there are many active projects.

Expected behavior: add a filter control to the Global Gantt view (at least by Status, mirroring the one that already exists in the Projects search) so the diagram can be narrowed down.