[TextArea] Set cursor position with mouse click

[LauraAubin]

Closes #2

What does this accomplish?

This PR implements a regular <textarea /> with the ability to click anywhere within the space to place the cursor. This allows you to bypass new lines and unchartered area so that you can start typing without the need to mash your space bar.

How is this done?

Setting the cursor in the y-axis requires us to use a consistent line-height CSS property and perform a quick calculation using the clicked y-coordinate to determine which line we are on:

  const selectedRow = mouseCoordinates?.y ? Number((mouseCoordinates?.y / 15).toFixed()) : 1;

We then add more new lines to the text area's state using \n if the clicked space is outside the bounds of our existing content. The cursor will automatically be placed on the last line.

In order to set the cursor in the x-axis,