docs: mark A4 workspace switching as complete

WAYLAND_ROADMAP.md

@@ -80,6 +80,7 @@ Three major libraries:
 - **Wave 2 complete**: 4 mechanical elimination tasks (A4.1, B.1, R.5, R.7)
 - C.1 skipped: XOR rubber-band drawing in `moveres.c` is inside `#if 0` — dead code
 - Native XDG client rendering fix: `surface_commit_listener` calls `wlr_output_schedule_frame()` on every buffer commit (commit 8d963e7)
+- **A4 Workspace switching**: map/unmap via vtable already worked; added workspace name badge overlay (pixman text rendering in WL_LAYER_OVERLAY, fade animation via new `workspace_badge_get_background` vtable slot)
 
 ---
 
@@ -92,7 +93,7 @@ Priority: HIGH — needed for daily-driver use.
 | A1 | ~~Stacking (raise/lower via scene graph)~~ | stacking.c, wlr_scene_node_raise/lower | ✅ Done |
 | A2 | ~~Window maximize~~ | actions.c, usable area calc | ✅ Done |
 | A3 | ~~Window shade (titlebar collapse)~~ | actions.c, frame buffer resize | ✅ Done |
-| A4 | Workspace switching (create/destroy/switch) | workspace.c, scene tree reparenting | Medium |
+| A4 | ~~Workspace switching (create/destroy/switch)~~ | workspace.c, scene tree reparenting | ✅ Done |
 | A5 | ~~Alt-Tab window cycling + switch panel~~ | cycling.c, switchpanel.c, vtable switchpanel_enter | Medium |
 | A6 | ~~Window iconification (minimize) + miniwindow~~ | icon.c, appicon.c, vtable icon_paint/icon_update_pixmap | Done |
 | A7 | Window placement algorithms (smart/cascade/random) | placement.c (may already work via vtable) | Low |
@@ -226,7 +227,7 @@ NOW (daily-driver basics):
   A1. Stacking (raise/lower)
   A2. ~~Maximize~~ ✅
   A3. ~~Shade~~ ✅
-  A4. Workspace switching
+  ~~A4. Workspace switching~~ ✅
   ~~A5. Alt-Tab cycling~~ ✅
   A6. Icon/minimize
   A7. Placement (verify)