docs: add model docs

packages/web/src/content/docs/docs/models.mdx

@@ -28,11 +28,9 @@ You can add custom providers by specifying the npm package for the provider and
   "$schema": "https://opencode.ai/config.json",
   "provider": {
     "openrouter": {
-      "npm": "@openrouter/ai-sdk-provider",
       "name": "OpenRouter",
-      "options": {},
       "models": {
-        "anthropic/claude-3.5-sonnet": {
+        "weirdo/some-weird-model": {
           "name": "Claude 3.5 Sonnet"
         }
       }