Clamp to the supported range and round to whole percentage points. Rounding matters because repeated ±0.1 steps accumulate float error (0.7 → 0.69999…), which would otherwise make equality checks like zoom === DEFAULT_ZOOM fail.
zoom === DEFAULT_ZOOM
Clamp to the supported range and round to whole percentage points. Rounding matters because repeated ±0.1 steps accumulate float error (0.7 → 0.69999…), which would otherwise make equality checks like
zoom === DEFAULT_ZOOMfail.