test(08-02): L5 overflow vector becomes a 3-node path

A 2-node graph has no degree>=2 candidates, so farthestPointAnchors
returns empty before any Dijkstra runs and never reaches the overflow
throw. Node 1 on a 3-node path is a candidate, so the selection pass
actually exercises the law.

routing/test/landmark.test.mjs

@@ -170,11 +170,16 @@ test("L4 asymmetry — reversed vs forward rows differ on an oneway graph", asyn
 test("L5 overflow throws — any label > 65000 quanta fails loud, naming the fix", async () => {
   const { landmarkTables, farthestPointAnchors, LANDMARK_MAX_QUANTA } = await loadLandmark();
   assert.equal(LANDMARK_MAX_QUANTA, 65000);
+  // 3-node path so node 1 is a degree-2 candidate — the anchor-selection
+  // pass actually runs (a 2-node graph has no candidates and returns
+  // empty before any Dijkstra).
   const input = {
-    nodeCount: 2,
+    nodeCount: 3,
     edges: [
       { from: 0, to: 1, seconds: 10, flags: 0 }, // floor(10/0.0001) = 100000 quanta
       { from: 1, to: 0, seconds: 10, flags: 0 },
+      { from: 1, to: 2, seconds: 10, flags: 0 },
+      { from: 2, to: 1, seconds: 10, flags: 0 },
     ],
     quantumS: 0.0001,
   };