test: add an E2E spec for the suspended (zoomed-out) interaction path

8. Add an E2E spec that exercises the suspended interaction path. The behaviour this PR fixes is
cross-layer and no spec covers it: `lodThreshold.spec.ts` predates this work, has no `@vue-nodes`
tag, and asserts `window.app.canvas.low_quality`, which is the classic renderer's own LOD. The new
clamp widens the gap by guaranteeing that fitting always lands above the threshold, and its own
comment says specs wanting simplified mode should set the zoom themselves, which none does. One
spec that sets the zoom below the threshold, asserts `[data-node-id]` has count 0 and the overlay is
attached, then clicks a known node position and asserts selection, would kill three of the four
surviving mutants at once.

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Found during round 3 review of #15031. Filed as a follow-up so it is not lost when that PR merges.