Collect visual feedback

Under project Features, Point is on by default. Turn on feedback to show Give feedback in the widget, and vision if the model should look at the screenshot image itself, not just its metadata. Vision costs more, so it's off by default.

Inputs and password fields are masked automatically. Add data-mango-mask to anything else:

<div class="account-balance" data-mango-mask>…</div>

Visitors click an element or drag a region, preview the masked capture, and send it with their message.

Feedback in the panel shows each item with its thumbnail, type, rating, page and selector. Set a status (new, triaged, planned, done, won't do), assign it, and let duplicates group by selector and page.