feat(anthropic): add Claude 4.5 Opus model support (#372)

Add support for claude-opus-4-5-20251101 model and update README
with all currently supported models.

Author: amondnet

plugins/anthropic/README.md

@@ -28,7 +28,7 @@ to the [official Vertex AI plugin](https://www.npmjs.com/package/@genkit-ai/vert
 ## Supported models
 
 The plugin supports the most recent Anthropic models:
-**Claude 3.7 Sonnet**, **Claude 3.5 Sonnet**, **Claude 3 Opus**, **Claude 3 Sonnet**, and **Claude 3 Haiku**.
+**Claude 4.5 Opus**, **Claude 4.5 Sonnet**, **Claude 4.5 Haiku**, **Claude 4 Opus**, **Claude 4 Sonnet**, **Claude 3.7 Sonnet**, **Claude 3.5 Sonnet**, **Claude 3.5 Haiku**, **Claude 3 Opus**, **Claude 3 Sonnet**, and **Claude 3 Haiku**.
 
 ## Installation
 

plugins/anthropic/src/claude.ts

@@ -254,6 +254,24 @@ export const claude45Haiku = modelRef({
   version: 'claude-haiku-4-5-20251001',
 });
 
+export const claude45Opus = modelRef({
+  name: 'claude-4-5-opus',
+  namespace: 'anthropic',
+  info: {
+    versions: ['claude-opus-4-5-20251101'],
+    label: 'Anthropic - Claude 4.5 Opus',
+    supports: {
+      multiturn: true,
+      tools: true,
+      media: true,
+      systemRole: true,
+      output: ['text'],
+    },
+  },
+  configSchema: AnthropicConfigSchema,
+  version: 'claude-opus-4-5-20251101',
+});
+
 export const SUPPORTED_CLAUDE_MODELS: Record<
   string,
   ModelReference<typeof AnthropicConfigSchema>
@@ -268,6 +286,7 @@ export const SUPPORTED_CLAUDE_MODELS: Record<
   'claude-4-opus': claude4Opus,
   'claude-4-5-sonnet': claude45Sonnet,
   'claude-4-5-haiku': claude45Haiku,
+  'claude-4-5-opus': claude45Opus,
 };
 
 /**

plugins/anthropic/src/index.ts

@@ -28,6 +28,7 @@ import {
   claude35Haiku,
   claude45Sonnet,
   claude45Haiku,
+  claude45Opus,
   claudeModel,
   SUPPORTED_CLAUDE_MODELS,
 } from './claude.js';
@@ -46,6 +47,7 @@ export {
   claude35Haiku,
   claude45Sonnet,
   claude45Haiku,
+  claude45Opus,
 };
 
 export interface PluginOptions {