fix(tui): apply log filter to full log list, not viewport window

viewLogsTab filtered logViewport.View() — the visible window — so the
entry count showed the window size and hidden lines reappeared while
scrolling. Filter and render now happen at content-set time from
engine.GetLogs(); the view only reads stored counts.

internal/tui/tui.go

@@ -121,6 +121,8 @@ type Model struct {
 
 	logViewport        viewport.Model
 	logFilterImportant bool
+	logTotal           int
+	logShown           int
 
 	historyViewport viewport.Model
 	historyChanges  []models.StateChange