feat(codev): M4 - matching 3 modes + boutons UI + animation force

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

components/codev/CodevGraph.vue

@@ -8,7 +8,21 @@
     </div>
 
     <!-- SVG D3 -->
-    <svg v-else ref="svgEl" class="codev-svg" />
+    <svg v-else ref="svgEl" class="codev-svg">
+      <defs>
+        <marker
+          id="arrow-solution"
+          viewBox="0 0 10 10"
+          refX="18"
+          refY="5"
+          markerWidth="6"
+          markerHeight="6"
+          orient="auto-start-reverse"
+        >
+          <path d="M 0 0 L 10 5 L 0 10 z" fill="#22c55e" />
+        </marker>
+      </defs>
+    </svg>
 
   </div>
 </template>
@@ -82,9 +96,9 @@ function buildLinks(nodes: SimNode[]): SimLink[] {
 }
 
 function linkColor(mode: string): string {
-  if (mode === 'solution') return '#1B4436'
-  if (mode === 'alliance') return '#3b82f6'
-  if (mode === 'surprise') return '#a855f7'
+  if (mode === 'solution') return '#22c55e'
+  if (mode === 'alliance') return '#f97316'
+  if (mode === 'surprise') return '#3b82f6'
   return '#ccc'
 }
 
@@ -132,8 +146,6 @@ function rebuildLinks() {
   currentLinks = buildLinks(currentNodes)
   if (!gLinks || !simulation) return
 
-  const r = nodeRadius.value
-
   const linkSel = gLinks
     .selectAll<SVGLineElement, SimLink>('line')
     .data(currentLinks, (d: SimLink) => {
@@ -149,7 +161,7 @@ function rebuildLinks() {
     .attr('stroke', d => linkColor(d.mode))
     .attr('stroke-width', d => 1 + d.score * 3)
     .attr('stroke-opacity', 0.7)
-    .attr('marker-end', null)
+    .attr('marker-end', d => d.mode === 'solution' ? 'url(#arrow-solution)' : null)
 }
 
 // ── Rendu complet ──────────────────────────────────────────────────────────
@@ -173,6 +185,7 @@ function render() {
     .attr('stroke', d => linkColor(d.mode))
     .attr('stroke-width', d => 1 + d.score * 3)
     .attr('stroke-opacity', 0.7)
+    .attr('marker-end', d => d.mode === 'solution' ? 'url(#arrow-solution)' : null)
 
   // Noeuds = groupe <g> par personne
   const nodeGroups = gNodes!