Limited Queue

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A circular queue that overrides the oldest data if trying to push a data when the queue is full.

All operations are of O(1) complexity, except the constructor with O(Vec::with_capacity).

Comparison

There is a similar library circular-queue I found, but without the basic peek and pop operations. The comparison for now is listed below:

	`LimitedQueue`	`circular-queue`
Algorithm	circular queue (front-rear, without additional element slot)	circular queue (based on `len` and `capacity` provided by `Vec`)
Element trait bound needed	No	-
`push`, size-related methods	✅	✅
`peek`, `pop` support	✅: `peek`✅: `pop`	❌
Indexing	✅- `[0, len)`- support `[idx]`- support `get(idx)`- optionally mutable (`[idx]`)	❌
Iterator	✅- `iter()` (DoubleEndedIterator)- `iter_mut()` (DoubleEndedIterator)	✅- both ways- optionally mutable
`clear` complexity	`O(1)`	`O(Vec::clear)`
`serde` support	❌ (TODO)	✅

We welcome any kinds of contributions, please don't be hesitate to submit issues & PRs.

This is a significant feature and stability release.

BREAKING (but good) CHANGE: pop() no longer requires the T: Default trait bound. This was achieved by refactoring the internal storage to Vec<Option<T>> and is verified by tests .
New Feature: Added iter_mut(), providing a mutable, double-ended iterator.
Enhancement: iter() now implements DoubleEndedIterator, allowing for reverse iteration (e.g., .iter().rev()).
Internal Refactor: push() and with_capacity() logic was rewritten to pre-allocate the internal Vec with None, simplifying the implementation and removing potential panic paths.
Fix: Corrected a logic bug in get(idx) that caused incorrect None returns.
Testing: Test suite was significantly expanded to cover all methods, edge cases (like capacity 0 and 1), and panic conditions, achieving 100% test coverage.

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