Fix: grid sampler bounds checking

[bashhack]

Summary

• Fix transcription error from Java ZXing where y == height was nudged to float64(height) instead of float64(height - 1)
• Add explicit math.IsNaN / math.IsInf rejection for Go 1.24+ where int(math.NaN()) changed from MinInt64 to 0, silently bypassing bounds checks
• Rewrite checkAndNudgePoints from a two-pass endpoint-only check to a single pass over all points, clamping moderate overshoot (within 5% of image dimension) instead of rejecting it
• Remove redundant px >= width || py >= height check in DefaultGridSampler.SampleGridWithTransform because BitMatrix.Get already returns false for out of bounds coordinates

Context

Perspective transforms may expectedly overshoot image edges by a few pixels. The old implementation rejected these outright, causing NotFoundException on valid QR codes. This proposed implementation clamps small overshoot to the nearest edge while still rejecting degenerate transforms (NaN, Inf, or far out of bounds).

Testing

[x] All existing test packages pass
[x] New tests added for NaN/Inf, clamping behavior, far-out-of-bounds rejection and interior points checking