fix(models): Add button, probe of managed models, delete list refresh

- ui.js: mount() now wraps non-node children in text nodes (like h()), so
  mount(el, "") no longer throws in appendChild — this is what broke the
  "Add model" form (applyDefaults cleared a status via mount(x,"")).
- probe_model: resolve managed local models too (they are synthesized into the
  registry, not [[models]]) — probing them no longer returns "model not found".
- models.js: await reload() after delete so the row is removed immediately.

Cargo.lock

@@ -285,7 +285,7 @@ checksum = "1d07550c9036bf2ae0c684c4297d503f838287c83c53686d05370d0e139ae570"
 
 [[package]]
 name = "cortiq-gateway"
-version = "0.2.10"
+version = "0.2.11"
 dependencies = [
  "anyhow",
  "arc-swap",