Maniphest expects the values of the ids URL parameter to be integers. Example: http://phorge.localhost/maniphest/?ids=1,2,3,4 to show a list of tasks with those IDs.
When passing monograms instead (T prefix, like T123 instead of 123), a cryptic message Expected a numeric scalar or null for %Ld conversion is shown.
Thus check if $this->taskIDs consists of integers only; if not throw a PhutilSearchQueryCompilerSyntaxException with an explanatory error message.
Closes T15838