feat(ui): add bounded workspace windows

registry/components.json

@@ -131,6 +131,22 @@
         "A draggable inspector moves by its header and remains clamped to the viewport."
       ]
     },
+    {
+      "id": "workspace-window",
+      "status": "baseline",
+      "package": "@nodedc/ui-react",
+      "exports": ["WorkspaceWindow", "WorkspaceWindowRect", "WorkspaceWindowProps"],
+      "domContract": ["nodedc-workspace-window"],
+      "summary": "Controlled modeless window for media, tools and synchronized views constrained to an application-owned workspace.",
+      "anatomy": ["controlled local rectangle", "title and optional status", "maximize and close actions", "scrollable body", "optional footer", "keyboard-accessible resize handle"],
+      "behavior": ["inline render without portal", "parent-bound dragging", "bottom-right resizing", "maximize within parent", "ResizeObserver reclamp", "pointer and keyboard geometry control", "application-owned activation and stacking"],
+      "rules": [
+        "The bounds element is an application-owned positioned and clipped workspace; WorkspaceWindow never escapes it or renders into document.body.",
+        "Rectangle, maximized state, visibility, activation and z-order are controlled by the application.",
+        "Use WorkspaceWindow for auxiliary views inside a stage; modal workflows and viewport inspectors continue to use Window.",
+        "Dragging and resizing remain clamped when the workspace changes size, including when it becomes smaller than the requested minimum."
+      ]
+    },
     {
       "id": "confirmation-modal",
       "status": "baseline",