TestDbFactory was redeclared as a private nested class in 40 test files,
NullServiceProvider and StubNotesApi in 14 each, DefaultStub in 5 — 73
declarations, all semantically identical (StubNotesApi differed only in
formatting and type qualification). They now live in TestDoubles.cs next to the
existing StubWorkerClient, which was already the shared-double pattern in this
project.
Slice 4/5 of task-numbers: TaskRowViewModel.Number renders as a dimmed
"#123" before the row title; DetailsIslandViewModel.TaskIdBadge now
shows "#123" instead of the unusable "#T<guid-prefix>" handle; and the
curated WorkerLog business events in TaskRunner, TaskMergeService, and
TaskResetService prefix their quoted title with "#<Number>".