feat(api): add haiku model (#333)

Author: stainless-bot

src/resources/messages.ts

@@ -394,6 +394,7 @@ export interface MessageCreateParamsBase {
     | (string & {})
     | 'claude-3-opus-20240229'
     | 'claude-3-sonnet-20240229'
+    | 'claude-3-haiku-20240307'
     | "claude-2.1'"
     | 'claude-2.0'
     | 'claude-instant-1.2';
@@ -620,6 +621,7 @@ export interface MessageStreamParams {
     | (string & {})
     | 'claude-3-opus-20240229'
     | 'claude-3-sonnet-20240229'
+    | 'claude-3-haiku-20240307'
     | "claude-2.1'"
     | 'claude-2.0'
     | 'claude-instant-1.2';