fix UBaseInput.vue call of "input" event for type=number with strings

• remove [numberEvent]="rounding" line, because handling both input and change create a mess. We need input (change on type)
• introduce internalValue property, because while we type, it might be not a valid value for model (not a number, for example), but still it shall be bound to input
• model getter for type=number uses internalValue
• model setter sets internalValue and converts string to number, for type=number