feat: unify object observation API

crates/wip-tui/README.md

@@ -80,7 +80,6 @@ All required actions are keyboard-accessible.
 | `←`/`h` | Collapse a node or move to its parent |
 | `Tab` | Cycle Tree → Selected Entry → Operations → History |
 | `r` | Reobserve the selected Entry and its direct subtree |
-| `+` | Double the selected node limit and retry an incomplete/truncated tree |
 | `c` | Cancel the newest retrieval; a dispatched operation is never presented as canceled |
 | `R` | Reconnect after connection failure |
 | `?` | Open help |
@@ -94,9 +93,9 @@ a second explicit Enter (or `e`) to execute once. There is no operation auto-ret
 ## Screen model
 
 - **Worldspace tree** starts at `/` and materializes direct children only when a
-  node is expanded. Text labels distinguish unloaded, loading, empty, stale,
-  failed, and truncated state; color is supplemental. A truncated node is never
-  presented as a complete tree.
+  node is expanded. Text labels distinguish unloaded, loading, empty, stale, and
+  failed state; color is supplemental. Every successful expansion is complete for
+  its requested depth.
 - **Selected Entry** shows only public WIP path, object name, description, ordered
   interfaces, and freshness. Validators, credentials, Host internals, and backend
   paths are deliberately hidden. If current metadata disappears, old text is not