fix(web): make provider deletion stick in the settings panel and model picker

Deleting a provider from the Providers panel looked like a no-op, and the
provider's models stayed in the model picker even after removing it from
config.toml by hand. Four defects lined up:

- The daemon answers DELETE /providers/{id} with 204 and no body, and the
  web transport parsed every response as JSON, so the delete always
  rejected client-side after the server had already applied it.
- The redesigned panel called the raw API without a catch and skipped the
  client facade, so the failure was silent and the model picker's
  providers+models were never reloaded.
- The background catalog refresh took one config snapshot, fetched over
  the network, then wrote the whole providers/models tables back, which
  resurrected any provider deleted in between. The write-back now
  reconciles against the live user config: providers removed meanwhile
  stay removed (their models too), providers added meanwhile are kept.
- Deletion filtered model rows on 'provider' only while resolution honours
  'provider_id' as well, so rows keyed that way outlived their provider.
  Every provider-scoped model filter now uses the same resolution.

The web client also reloads providers and models when the daemon reports
a config change that touches them, so an external config.toml edit is
reflected in the picker without a page reload.

Author: elkaix

.changeset/provider-delete-sticks.md

@@ -0,0 +1,5 @@
+---
+"@pymodel/pythinker-code": patch
+---
+
+Fix deleting a provider in the web and desktop settings: the provider and its models now disappear from the model picker, a failed delete shows an error, and a background catalog refresh no longer brings a deleted provider back.

apps/pythinker-code/dist-web/.web-bundle-manifest.json

@@ -1,4 +1,4 @@
 {
-  "sourceHash": "135af31b82e0a89e3644936171b91c29d9880f1112d9b9046c4871da90618387",
+  "sourceHash": "f73a79a727e58eba289d63e39ddc3f5569567bbfcbec2b363d586b2efd8c27ff",
   "sourceFileCount": 422
 }