Add the workspace coding agent, launch gate, and composable locks

- run a singleton Codex App Server adapter in each dev workspace
- gate Web Studio with a reloadable fragment-token to HttpOnly-session exchange
- add ChatGPT device login and streamed chat to Web Studio
- isolate authoring access in a declarative NixOS service account
- split Web Studio canvas, object, panel, and model concerns
- check generated Quixos protocol clients for drift
- resolve same-repository quixos.lock fragments deterministically
- preserve the collaborative canvas gesture fixes

test/fixtures/react-component.interface.qx

@@ -0,0 +1,5 @@
+interface ReactComponent id "interface:org.quixos.web-studio.react-component" revision "interface:org.quixos.web-studio.react-component@1" {
+  value props id "member:org.quixos.web-studio.react-component:props" : string {
+    get id "operation:org.quixos.web-studio.react-component:props:get";
+  }
+}