ollamarunner: Use correct constant to remove cache entries

The correct constant to remove all entries to the end of the sequence
for the Ollama engine is math.MaxInt32. -1 is used by the old engine.

The impact of this is currently minimal because it would only occur
in situations that are not supported by the implemented models or
rarely used options.

runner/ollamarunner/cache.go

@@ -284,7 +284,7 @@ func (c *InputCache) ShiftCacheSlot(slot *InputCacheSlot, numKeep int32) error {
 			copy(newInputs[numKeep:], slot.Inputs[numKeep+discard:])
 
 			// Reset the cache
-			_ = c.cache.Remove(slot.Id, 0, -1)
+			_ = c.cache.Remove(slot.Id, 0, math.MaxInt32)
 			slot.Inputs = []input.Input{}
 
 			// Return error with inputs that need to be reprocessed