Add stub implementation for my best friend, the humble circular queue

Add stubs for a custom circular queue implementation for the historical data in the parking repo

src/types/CircularQueue.ts

@@ -0,0 +1,27 @@
+export class CircularQueue<T> {
+  private startIndex: number;
+  private endIndex: number;
+  private _data: T[];
+
+  constructor(
+    size: number,
+  ) {
+    // See the Mozilla documentation on sparse arrays (*not* undefined values)
+    // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Indexed_collections#sparse_arrays
+    this._data = new Array<T>(size);
+    this.startIndex = 0;
+    this.endIndex = size - 1;
+  }
+
+  appendWithSorting = (
+    data: T,
+    sortingCallback: ((a: T, b: T) => number) | undefined
+  ) => {
+    // In case something is added that's not sorted, the sortingCallback
+    // will be used to sort
+  }
+
+  popFront = (data: T) => {
+
+  }
+}