Direct Ring Buffer has uninitialized memory exposure in create_ring_buffer

Summary

The safe function `create_ring_buffer` allocates a buffer using `Vec::with_capacity` followed by `set_len`, creating a `Box<[T]>` containing uninitialized memory. This leads to undefined behavior when functions like `write_slices` create typed slices (e.g., `&mut [bool]`) over the uninitialized memory, violating Rust's validity invariants. The issue has been confirmed using Miri. Fixed in version 0.2.2 by using `resize_with` to properly initialize the buffer with `T::default()`, adding a `T: Default` bound to ensure sound initialization.