fix(gateway): declare cwd_explicit on the session.create contract

The desktop ships cwd_explicit provenance with session.create (#52589),
but the wire contract (extra=forbid) rejected the unknown key, so every
remote-mode create failed with 'out of sync (different versions)' and the
composer never accepted the draft (Desktop core E2E remote-topology).
Local-backend lanes never sent it (a bare new chat is detached, no cwd).

Regenerate the shared contract TS + OpenRPC from the updated registry.

apps/shared/src/gateway-contract.generated.ts

@@ -2762,6 +2762,7 @@ export interface SessionCreateParams {
   cols?: number | null
   source?: string | null
   cwd?: string | null
+  cwd_explicit?: boolean | null
   messages?: SeedMessage[] | null
   parent_session_id?: string | null
   title?: string | null

apps/shared/src/gateway-contract.openrpc.json

@@ -28659,6 +28659,18 @@
             "default": null,
             "title": "Cwd"
           },
+          "cwd_explicit": {
+            "anyOf": [
+              {
+                "type": "boolean"
+              },
+              {
+                "type": "null"
+              }
+            ],
+            "default": null,
+            "title": "Cwd Explicit"
+          },
           "messages": {
             "anyOf": [
               {

tui_gateway/contracts/sessions.py

@@ -119,6 +119,9 @@ class SessionCreateParams(ProfileParams):
     cols: int | None = None
     source: str | None = None
     cwd: str | None = None
+    # #52589: provenance for ``cwd`` — true only for a deliberate workspace pick;
+    # an inherited app-global workspace must yield to a named profile's terminal.cwd.
+    cwd_explicit: bool | None = None
     messages: list[SeedMessage] | None = None
     parent_session_id: str | None = None
     title: str | None = None