fix(array): respect negative step in range() to avoid an infinite loop

[yfwmaniish]

Bug

Closes #49.

range(start, stop, step) loops forever when step is negative, because the loop condition is hard-coded to the positive direction:

let current = start
while (current < stop) {
  arr.push(current)
  current += step || 1   // step = -1 → current keeps decreasing, always < stop
}

range(1, 5, -1) // 🔁 infinite loop (hangs the process)

Fix

Advance in the step's direction, so a negative step counts down and simply produces an empty array when the direction can't reach stop:

step = step || 1 // keep the historical zero-step fallback of 1
if (step > 0) {
  for (let current = start; current < stop; current += step)
    arr.push(current)
}
else {
  for (let current = start; current > stop; current += step)
    arr.push(current)
}

Behavior

call	before	after
range(1, 5, -1)	🔁 infinite loop	[]
range(5, 1, -1)	🔁 infinite loop	[5, 4, 3, 2]
range(10, 2, -2)	🔁 infinite loop	[10, 8, 6, 4]
range(2, 10, 2)	[2, 4, 6, 8]	[2, 4, 6, 8] (unchanged)
range(5) / range(2, 5)	unchanged	unchanged

Positive-step and zero-step behavior is unchanged; negative steps now count down (matching the intuitive/Python-like semantics) instead of hanging.

Tests

Extended the range test with the reporter's case and descending ranges. Full suite passes (39 passed), lint clean.

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