fix(graph): honor zero Every-node spring stiffness

Author: Coding-Dev-Tools

engraphis/dashboard_assets/engraphis-graph-every-worker.js

@@ -223,7 +223,9 @@
     const scaledSpacing = SPACING * MAP_SCALE;
     const spring = Number.isFinite(Number(settings.springStiffness))
       ? Math.max(0, Math.min(100 / 32, Number(settings.springStiffness))) : 1;
-    const springScale = 0.35 + 0.65 * spring;
+    // springStiffness is already a normalized multiplier from the dashboard. Preserve its
+    // zero endpoint so the Link spring control can actually disable pair attraction.
+    const springScale = spring;
     const rest = Math.max(scaledSpacing * 1.9, Number(settings.link) * 1.6 * (MAP_SCALE * 0.55));
     for (let edge = 0; edge < model.totalLinks; edge += 1) {
       const a = model.sources[edge], b = model.targets[edge];

tests/test_graph_every_asset.py

@@ -203,6 +203,38 @@ def test_worker_settling_resistance_keeps_high_end_distinct() -> None:
     assert samples["14"] != samples["15"]
 
 
+def test_worker_honors_zero_link_spring_stiffness() -> None:
+    """A zero Link spring value must remove pair attraction, not leave a residual floor."""
+    script = """
+const nodes = [
+  { id: 'a', community_id: 'c' },
+  { id: 'b', community_id: 'c' },
+];
+send({ type: 'prepare', payload: { nodes, links: [{ source: 'a', target: 'b' }] } });
+const waitForFit = (start, callback) => {
+  const tick = () => {
+    const fit = messages.slice(start).find(item => item.type === 'layout' && item.fit === true);
+    if (fit) return callback(fit.positions);
+    setTimeout(tick, 10);
+  };
+  tick();
+};
+setTimeout(() => {
+  const seeded = latest('preview').positions.slice();
+  const start = messages.length;
+  send({ type: 'settings', settings: {
+    repel: 0, gravity: 0, springStiffness: 0, damping: 1,
+  }, relayout: true, fit: true });
+  waitForFit(start, positions => {
+    const delta = Math.max(...positions.map((value, index) => Math.abs(value - seeded[index])));
+    console.log(JSON.stringify({ delta }));
+  });
+}, 50);
+"""
+    report = _run_worker(script)
+    assert report["delta"] == 0
+
+
 def test_renderer_is_webgl2_only_without_live_simulation_or_canvas_fallback() -> None:
     renderer = RENDERER.read_text(encoding="utf-8")
     assert "getContext('webgl2'" in renderer