refactor: migrate tasks view to lipgloss/table for visual consistency

Replace hand-rolled fmt.Sprintf table rendering in the tasks view with
charmbracelet/lipgloss/table using StyleFunc, matching the queue view
pattern. This gives the tasks view stable column widths across scroll,
per-cell status coloring, selection highlighting with background color,
and column border support (toggled via 'o' from queue view).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: mariusvniekerk