Merge branch 'worktree/web-carrier-chain' into worktree/web-ask-user-question

Restack the ask-user domain layer onto the carrier-chain architecture
branch. Conflict policy: runtime and ui-conversation take the
carrier-chain side (master sessions shape, dual-kind PendingCard,
'internal' envelope shell tests); the 'cancelled' wire code and its
semantics tests stay in apiproxy + ui-question (domain layer); the
smoke fixture keeps the nine-bundle success pass with the resident
question round over the carrier-chain first-describe shape.

packages/host/runtime/tsconfig.json

@@ -62,6 +62,9 @@
     {
       "path": "../../fs/tool-fs-search"
     },
+    {
+      "path": "../../context/workspace-context"
+    },
     {
       "path": "../../llm/token-meter"
     },