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/cerebras.js

@@ -1,46 +1,30 @@
 export default {
-  "id": "cerebras",
-  "alias": "cerebras",
+  id: "cerebras",
+  alias: "cerebras",
   display: {
-      "name": "Cerebras",
-      "icon": "memory",
-      "color": "#FF4F00",
-      "textIcon": "CB",
-      "website": "https://www.cerebras.ai",
-      "notice": {
-          "apiKeyUrl": "https://cloud.cerebras.ai/platform"
-      }
+    name: "Cerebras",
+    icon: "memory",
+    color: "#FF4F00",
+    textIcon: "CB",
+    website: "https://www.cerebras.ai",
+    notice: {
+      apiKeyUrl: "https://cloud.cerebras.ai/platform",
+    },
   },
   category: "apikey",
-  "transport": {
-    "baseUrl": "https://api.cerebras.ai/v1/chat/completions",
-    "validateUrl": "https://api.cerebras.ai/v1/models",
-    "quirks": { "dropClientMetadata": true }
+  transport: {
+    baseUrl: "https://api.cerebras.ai/v1/chat/completions",
+    validateUrl: "https://api.cerebras.ai/v1/models",
+    quirks: {
+      dropClientMetadata: true,
+    },
   },
-  "models": [
-    {
-      "id": "gpt-oss-120b",
-      "name": "GPT OSS 120B"
-    },
-    {
-      "id": "zai-glm-4.7",
-      "name": "ZAI GLM 4.7"
-    },
-    {
-      "id": "llama-3.3-70b",
-      "name": "Llama 3.3 70B"
-    },
-    {
-      "id": "llama-4-scout-17b-16e-instruct",
-      "name": "Llama 4 Scout"
-    },
-    {
-      "id": "qwen-3-235b-a22b-instruct-2507",
-      "name": "Qwen3 235B A22B"
-    },
-    {
-      "id": "qwen-3-32b",
-      "name": "Qwen3 32B"
-    }
-  ]
+  models: [
+    { id: "gpt-oss-120b", name: "GPT OSS 120B" },
+    { id: "zai-glm-4.7", name: "ZAI GLM 4.7" },
+    { id: "llama-3.3-70b", name: "Llama 3.3 70B" },
+    { id: "llama-4-scout-17b-16e-instruct", name: "Llama 4 Scout" },
+    { id: "qwen-3-235b-a22b-instruct-2507", name: "Qwen3 235B A22B" },
+    { id: "qwen-3-32b", name: "Qwen3 32B" },
+  ],
 };