fix(tui): maint tab min widths fit 80-column terminals

Reduce minimums so fixedMin=51 (was 71). At narrow: compact headers (ST, MON).
At wide: full headers (STATUS, MONITORS, STARTED) with expanded widths.

internal/tui/tab_maint.go

@@ -99,12 +99,12 @@ func (m Model) viewMaintTab() string {
 
 	cols := []colDef{
 		{"#", "#", 4, 4, false},
-		{"TITLE", "TITLE", 12, 28, true},
+		{"TITLE", "TITLE", 10, 28, true},
 		{"TYPE", "TYPE", 13, 14, false},
-		{"MON", "MONITORS", 15, 22, false},
-		{"STATUS", "STATUS", 11, 12, false},
-		{"START", "STARTED", 14, 16, false},
-		{"ENDS", "ENDS", 14, 16, false},
+		{"MON", "MONITORS", 10, 22, false},
+		{"ST", "STATUS", 8, 12, false},
+		{"START", "STARTED", 8, 16, false},
+		{"ENDS", "ENDS", 8, 16, false},
 	}
 	headers, widths := m.computeTableLayout(cols, 0)
 	titleW := widths[1]