fix overlay label collisions: common right-gutter anchor + leaders

End-labels sat on the line termini (2-arm figs) and piled up bottom-left on
ragged-length multi-arm overlays (substrate, where arms end at different steps).
Now all labels anchor at one gutter x with a leader fanning back to each line's
actual end, y-de-collided. Added right margin so the gutter is clear.

Co-Authored-By: Claudypoo <288921227+claudypoo@users.noreply.github.com>

scripts/plot_dynamics.py

@@ -382,16 +382,22 @@ def _overlay_panel(ax, by_arm, arms, key, *, label, with_onset, label_arms, ylim
     if not label_arms:                      # other panel shares colours -- redundant ink
         return
     ends.sort(key=lambda e: e[0])           # bottom-to-top by endpoint
-    gap = 0.052 * (ylim[1] - ylim[0])       # min y-separation, scaled to the range
+    gap = 0.06 * (ylim[1] - ylim[0])        # min y-separation, scaled to the range
+    xmax = max(e[1] for e in ends)
+    dx = 0.035 * (xmax - ax.get_xlim()[0])  # horizontal clearance off the line end
+    x_lab = xmax + dx                       # ALL labels share one gutter x, leaders fan back
+    ax.set_xlim(right=xmax + dx * 3.4)      # right margin so labels sit clear in the gutter
     placed = []
     for y, x, arm, color, is_zero in ends:
         y_lab = y if not placed else max(y, placed[-1] + gap)
         placed.append(y_lab)
         text = arm_label(arm) + (r" $\equiv 0$" if is_zero else "")
-        arrow = dict(arrowstyle="-", color=color, lw=0.5, shrinkA=0, shrinkB=0)
-        ax.annotate(text, xy=(x, y), xytext=(x + 1.0, y_lab), textcoords="data",
-                    color=color, fontsize=8, va="center",
-                    arrowprops=arrow if abs(y_lab - y) > 1e-3 else None)
+        # Common gutter x + leader back to each line's actual end: ragged run lengths
+        # otherwise scatter labels mid-plot onto other arms' lines (collision test).
+        arrow = dict(arrowstyle="-", color=color, lw=0.5, shrinkA=0, shrinkB=2)
+        ax.annotate(text, xy=(x, y), xytext=(x_lab, y_lab), textcoords="data",
+                    color=color, fontsize=8, va="center", annotation_clip=False,
+                    arrowprops=arrow)
 
 
 def plot_hack_overlay(runs: list[dict], out: Path) -> None: