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/named.interface.qx

@@ -0,0 +1,7 @@
+interface Named id "interface:named" revision "interface:named@1" {
+  value name id "member:named:name" : string {
+    get id "operation:named:name:get";
+    set id "operation:named:name:set";
+    watch start id "operation:named:name:watch-start" stop id "operation:named:name:watch-stop";
+  }
+}