feat(draworder): cross-type draw order + context menu

DRAWORDER now affects rendering immediately (bump geometry epoch so the
sort cache rebuilds) and front/back anchor to the block's full effective
sort range instead of only existing table entries, so bring-to-front
actually lands on top. The render fallback sorts table-absent entities by
their own handle.

Draw order now applies across entity types, not just within a type. A
per-entity draw-order rank (SortEntitiesTable override or own handle,
ranked per block) is encoded as a small signed clip-z bias in the wire,
hatch, image, and 3DFACE pipelines. The shared LessEqual depth buffer then
orders fills, lines, rasters and 2D solids against each other regardless of
pass order — without touching model coordinates. 3D meshes keep real
geometric depth; wipeouts stay always-on-top.

Adds a Draw Order submenu to the viewport context menu (Bring to Front,
Send to Back, Bring Above/Send Under Object). The above/under items run an
interactive reference-object pick, then reorder the captured selection.

Co-Authored-By: Claude Opus 4.8 <[email protected]>

src/modules/home/draw/hatch.rs

@@ -121,6 +121,7 @@ impl HatchCommand {
             scale: 1.0,
             world_origin: [0.0; 2],
             vp_scissor: None,
+            draw_depth: 0.0,
         }
     }
 }
@@ -258,6 +259,7 @@ impl GradientCommand {
             scale: 1.0,
             world_origin: [0.0; 2],
             vp_scissor: None,
+            draw_depth: 0.0,
         }
     }
 }
@@ -408,6 +410,7 @@ impl CadCommand for BoundaryCommand {
                     scale: 1.0,
                     world_origin: [0.0; 2],
                     vp_scissor: None,
+                    draw_depth: 0.0,
                 };
                 return CmdResult::CommitHatch(model);
             }