refactor(registry): B2 migrate to LiteLLM-style schema — unified models[] with kind field

- 71 registry files: flat `media.*Config.models` → `models[]` with `kind` field
- `media` wrapper removed → serviceKinds, *Config fields promoted top-level
- `type` field renamed to `kind` (llm/image/tts/stt/embedding/embedding/video/music)
- providers/index.js: PROVIDER_MEDIA now built from flat top-level media fields
- shared/constants/providers.js: buildProviderEntry reads flat top-level media fields
- route /v1/models: modelKind() uses kind||type; removed subConfig merge block
- models/info route: removed sub-config fallback lookup (all models in PROVIDER_MODELS)
- ttsProviders/index.js: synthesizeViaConfig reads tts models from PROVIDER_MODELS
- test-models route, helpers.js, validate route: kind||type compat
- Baselines: PROVIDERS 62/62 ✅, Alias 90/90 ✅

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

open-sse/providers/registry/xai.js

@@ -1,60 +1,42 @@
-
 export default {
-  "id": "xai",
-  "alias": "xai",
+  id: "xai",
+  alias: "xai",
   display: {
-      "name": "xAI (Grok)",
-      "icon": "auto_awesome",
-      "color": "#1DA1F2",
-      "textIcon": "XA",
-      "website": "https://x.ai",
-      "notice": {
-          "apiKeyUrl": "https://console.x.ai"
-      }
+    name: "xAI (Grok)",
+    icon: "auto_awesome",
+    color: "#1DA1F2",
+    textIcon: "XA",
+    website: "https://x.ai",
+    notice: {
+      apiKeyUrl: "https://console.x.ai",
+    },
   },
   category: "apikey",
+  authModes: [
+    "oauth",
+    "apikey",
+  ],
   hasOAuth: true,
-  authModes: ["oauth","apikey"],
-  "transport": {
-    "baseUrl": "https://api.x.ai/v1/chat/completions",
-    "validateUrl": "https://api.x.ai/v1/models",
-    "responsesUrl": "https://api.x.ai/v1/responses",
-    "clientId": "b1a00492-073a-47ea-816f-4c329264a828",
-    "tokenUrl": "https://auth.x.ai/oauth2/token",
-    "refreshUrl": "https://auth.x.ai/oauth2/token"
+  transport: {
+    baseUrl: "https://api.x.ai/v1/chat/completions",
+    validateUrl: "https://api.x.ai/v1/models",
+    responsesUrl: "https://api.x.ai/v1/responses",
+    clientId: "b1a00492-073a-47ea-816f-4c329264a828",
+    tokenUrl: "https://auth.x.ai/oauth2/token",
+    refreshUrl: "https://auth.x.ai/oauth2/token",
   },
-  media: {
-    serviceKinds: ["llm", "imageToText", "webSearch", "image"],
-    searchViaChat: { defaultModel: "grok-4.20-reasoning", endpoint: "https://api.x.ai/v1/responses", pricingUrl: "https://x.ai/api#pricing" },
-    imageConfig: { baseUrl: "https://api.x.ai/v1/images/generations", bodyFields: ["model", "prompt", "n", "response_format"] },
-    authModes: ["oauth", "apikey"],
-    hasOAuth: true
+  models: [
+    { id: "grok-4", name: "Grok 4" },
+    { id: "grok-4-fast-reasoning", name: "Grok 4 Fast Reasoning" },
+    { id: "grok-code-fast-1", name: "Grok Code Fast" },
+    { id: "grok-3", name: "Grok 3" },
+    { id: "grok-2-image-1212", name: "Grok 2 Image", params: ["n","response_format"], kind: "image" },
+  ],
+  serviceKinds: ["llm","imageToText","webSearch","image"],
+  imageConfig: { baseUrl: "https://api.x.ai/v1/images/generations", bodyFields: ["model","prompt","n","response_format"] },
+  searchViaChat: {
+    defaultModel: "grok-4.20-reasoning",
+    endpoint: "https://api.x.ai/v1/responses",
+    pricingUrl: "https://x.ai/api#pricing",
   },
-  "models": [
-    {
-      "id": "grok-4",
-      "name": "Grok 4"
-    },
-    {
-      "id": "grok-4-fast-reasoning",
-      "name": "Grok 4 Fast Reasoning"
-    },
-    {
-      "id": "grok-code-fast-1",
-      "name": "Grok Code Fast"
-    },
-    {
-      "id": "grok-3",
-      "name": "Grok 3"
-    },
-    {
-      "id": "grok-2-image-1212",
-      "name": "Grok 2 Image",
-      "type": "image",
-      "params": [
-        "n",
-        "response_format"
-      ]
-    }
-  ]
 };