feat: add RunArray::new_unchecked and RunArray::into_parts

[rluvaton]

Which issue does this PR close?

N/A

Rationale for this change

Allow to make easy changes without validation (for example replace the values)

What changes are included in this PR?

added 2 functions

Are these changes tested?

yes

Are there any user-facing changes?

yes new functions

[Jefffrey]

Do we need to add force validate here like for other arrays

arrow-rs/arrow-array/src/array/dictionary_array.rs

Lines 332 to 336 in 765c5b7

	pub unsafe fn new_unchecked(keys: PrimitiveArray<K>, values: ArrayRef) -> Self {
	if cfg!(feature = "force_validate") {
	return Self::new(keys, values);
	}

arrow-rs/arrow-array/src/array/byte_array.rs

Lines 162 to 171 in 765c5b7

	pub unsafe fn new_unchecked(
	offsets: OffsetBuffer<T::Offset>,
	values: Buffer,
	nulls: Option<NullBuffer>,
	) -> Self {
	if cfg!(feature = "force_validate") {
	return Self::new(offsets, values, nulls);
	}
	Self {
	data_type: T::DATA_TYPE,

[alamb]

I agree -- we should make REE consistent with other arrays