Should the fullstop go inside or outside the brackets for Harvard in-line citations?
Full stops and periods should always go outside parenthetical references. The only time a stop should be "inside" a citation is when you are using superscript references, in which case the numbers normally appear after punctuation marks (at least in US based journals).

The reason is that the punctuation mark is not part of the citation itself. Therefore it should not be buried "inside" the citation.