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/cohere.js

@@ -1,34 +1,24 @@
-
 export default {
-  "id": "cohere",
-  "alias": "cohere",
+  id: "cohere",
+  alias: "cohere",
   display: {
-      "name": "Cohere",
-      "icon": "hub",
-      "color": "#39594D",
-      "textIcon": "CO",
-      "website": "https://cohere.com",
-      "notice": {
-          "apiKeyUrl": "https://dashboard.cohere.com/api-keys"
-      }
+    name: "Cohere",
+    icon: "hub",
+    color: "#39594D",
+    textIcon: "CO",
+    website: "https://cohere.com",
+    notice: {
+      apiKeyUrl: "https://dashboard.cohere.com/api-keys",
+    },
   },
   category: "apikey",
-  "transport": {
-    "baseUrl": "https://api.cohere.ai/v1/chat/completions",
-    "validateUrl": "https://api.cohere.ai/v1/models"
+  transport: {
+    baseUrl: "https://api.cohere.ai/v1/chat/completions",
+    validateUrl: "https://api.cohere.ai/v1/models",
   },
-  "models": [
-    {
-      "id": "command-r-plus-08-2024",
-      "name": "Command R+ (Aug 2024)"
-    },
-    {
-      "id": "command-r-08-2024",
-      "name": "Command R (Aug 2024)"
-    },
-    {
-      "id": "command-a-03-2025",
-      "name": "Command A (Mar 2025)"
-    }
-  ]
+  models: [
+    { id: "command-r-plus-08-2024", name: "Command R+ (Aug 2024)" },
+    { id: "command-r-08-2024", name: "Command R (Aug 2024)" },
+    { id: "command-a-03-2025", name: "Command A (Mar 2025)" },
+  ],
 };