refactor(open-sse): registry consolidation + DRY media/oauth/adhoc cleanup

- Single-source registry: oauth clientId/tokenUrl, usage URLs, image/embed
  configs, search defaultModel, codex fixedPort, google token url derive.
- Remove 29 unused OmniRoute providers (registry 100→71); media intact.
- De-adhoc: codex literals → registry format/oauth flags; reasoningInject,
  image/embed openrouter headers + xai bodyFields config-driven.
- Add REGISTRY_TEMPLATE.js + expand PROVIDER_DEFAULTS/schema JSDoc.
- Baselines updated; PROVIDERS 62 + alias 90 byte-for-byte, golden snapshots.

Co-authored-by: Cursor <cursoragent@cursor.com>

open-sse/providers/registry/sdwebui.js

@@ -1,6 +1,15 @@
+
 export default {
   "id": "sdwebui",
   "alias": "sdwebui",
+  display: {
+      "name": "SD WebUI",
+      "icon": "brush",
+      "color": "#FF7043",
+      "textIcon": "SD",
+      "website": "https://github.com/AUTOMATIC1111/stable-diffusion-webui"
+  },
+  category: "apikey",
   "transport": null,
   "models": [
     {