Incorrect uses of <label> found throughout the UI

[leafty]

The <label> element is specifically designed to label form fields and should only be used for that purpose.

See also: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/label

Most notably, incorrect <label> elements create bugs in the new session page, where clicking on "Branch" or "Commit" triggers clicking on the "refresh" button.

Fix: Use <label> only to label form field and always specify for= to target the desired field. Other elements should use <div> or <div class="form-label"> instead.