Implement ideas from T96297: - Fix "invalid axis settings" (both forward & up along the same direction) validation: now similar to the Python based code, when invalid axis is applied, the other axis is changed to not conflict. - Make axis enums be expanded inside the row, similar to Collada UI. - Move "selected only" near the top, similar to how it's in Collada, USD, FBX and glTF export UIs. - Move animation export options to the bottom.