docs(backend): record dead wire contract entries

src-tauri/AGENTS.md

@@ -24,6 +24,14 @@ These rules supplement the repository's root `AGENTS.md`.
    status strings pinned by the golden tests. Status additions or changes
    require frontend and backend changes in the same PR and an updated golden
    list; this protects the wire contract. No exceptions.
+
+    Known dead wire entries, recorded here and intentionally kept (no tracking
+    issue): the `config_validate::*` statuses whose frontend handlers never
+    receive a backend send (`core_change`, `stdout_error`, `yaml_key_error`,
+    `yaml_error`, `merge_key_error`, `merge_error`), and `set_config::ok`,
+    sent by the backend with no frontend handler. Each variant carries its own
+    comment in `NoticeStatus`. Removal requires a same-PR frontend change and a
+    golden-list update.
 5. **Preserve lock order.** The order is `config_write` before
    `config_update_in_progress` before `lifecycle_lock`. Patch callers must use
    the executor's guarded claim instead of independently combining these locks;