fix: begin of life arrow

src/core/draw/sequence.typ

@@ -130,8 +130,8 @@
     let par = ctx.participants.at(i2)
     let m = measure(box(par.display-name))
     let f = if i1 > i2 {-1} else {1}
-    end-info.x -= (m.width + PAR-PAD.last() * 2) / 2pt * f
-    (par.draw)(par, y: end-info.y)
+    end-info.x -= (m.width / 2 / 1pt - 1.5) * f
+    (par.draw)(par, y: end-info.y - m.height / 1pt)
   }
 
   end-info.ll-lvl = ctx.lifelines.at(i2).level * LIFELINE-W / 2