2.0.2: Let testers arrange findings by hand, and report in that order (#25)

The assessment screen and the generated report now both follow a single
display order, and the tester can rearrange it by dragging rows.

Severity is applied when a finding is created rather than when the list is
sorted: a new finding (or one carried forward, or one whose severity changes)
is placed after the last finding that is at least as severe. An untouched
list therefore still reads Critical to Informational, but anything moved by
hand stays exactly where it was put — including the occasional High placed
above a Critical, which the old severity-first sort silently undid in the
report. A one-off migration renumbers existing findings the same way; on the
dev database it reproduces the old report order for every assessment.

A "reset to severity order" action appears only once something sits above a
more severe finding. Reorders broadcast to other viewers of the assessment
as before, and the live refresh is held while a drag is in progress.

Also on the finding list: each row's left border takes its severity colour
(the accent when selected), and the form panel no longer draws a scrollbar.

Signed-off-by: Josh <ascetik@gmail.com>