v0.7.4

• Hovering a conversation now highlights it with a rounded panel inset from
  the list's edges instead of a full-width band; selected and open rows use
  the same shape, as do drafts and outbox rows.
• The thread list no longer paints a blue bar along the current row's left
  edge — neither on the last clicked conversation nor while moving through
  the list with the arrow keys.
• The view header no longer draws a bottom border — the bar sits flush above
  the list for a calmer top edge. The border still appears while searching,
  where it doubles as the search field's focus outline.