Two tsc errors surfaced by a later tsc run:
1. browser-image-search-fetcher.test.ts — imported `beforeEach`
but never used; also `spy.mock.calls[0]` typed as empty tuple
since vi.fn()'s signature isn't inferred. Cast via `unknown` +
explicit tuple shape.
2. chart-builders-visual-smoke.test.ts — custom-dimensions case
passed `width`/`height` to buildChartLine. The real shape is
`point_spacing` + `chart_height`. Fixed the test to use the
actual param names (test itself wasn't broken, just the type).
42b6492404