Add CAP_RIBS toggle to enable/disable retention ribs

cable_cap.scad

@@ -42,6 +42,7 @@ SCREEN_EXPLODE    = 0;     // mm to pull display toward X+ in preview
 
 // --- Slip-Fit Cap (X+ end) ---
 SHOW_CAP    = true;   // show cap in preview
+CAP_RIBS    = true;   // include retention ribs in cap
 CAP_PAD     = 4.0;   // Min cap bore depth
 CAP_ENGAGE  = CAP_PAD + 6.0;   // sleeve engagement length over case exterior (X)
 CAP_WALL    = 1.5;   // sleeve and end-wall thickness
@@ -199,9 +200,10 @@ module cable_cap() {
     }
 
     // Retention ribs — flush with X- face, full cap height, 2×2 mm, just outside FPC pocket
-    for (rib_dy = [fpc_pkt_y - CAP_WALL, fpc_pkt_y + fpc_pkt_yw])
-        translate([CAP_ENGAGE - CAP_PAD, rib_dy, 0])
-            cube([CAP_WALL, CAP_WALL, _cap_h]);
+    if (CAP_RIBS)
+        for (rib_dy = [fpc_pkt_y - CAP_WALL, fpc_pkt_y + fpc_pkt_yw])
+            translate([CAP_ENGAGE - CAP_PAD, rib_dy, 0])
+                cube([CAP_WALL, CAP_WALL, _cap_h]);
 
     // Chamfer tab: extends window bezel chamfer across the gap to the cap X- face
     hull() {