chore(deps): upgrade openai-go from v1.12.0 to v3.21.0

Update to latest major version of the official OpenAI Go SDK.
Fix breaking change: FunctionCallOutput.Output is now a union type
(ResponseInputItemFunctionCallOutputOutputUnionParam) instead of string.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

go.mod

@@ -4,6 +4,7 @@ go 1.24.0
 
 require (
 	github.com/adhocore/gronx v1.19.6
+	github.com/anthropics/anthropic-sdk-go v1.22.1
 	github.com/bwmarrin/discordgo v0.29.0
 	github.com/caarlos0/env/v11 v11.3.1
 	github.com/chzyer/readline v1.5.1
@@ -11,16 +12,15 @@ require (
 	github.com/gorilla/websocket v1.5.3
 	github.com/larksuite/oapi-sdk-go/v3 v3.5.3
 	github.com/open-dingtalk/dingtalk-stream-sdk-go v0.9.1
+	github.com/openai/openai-go/v3 v3.21.0
 	github.com/tencent-connect/botgo v0.2.1
 	golang.org/x/oauth2 v0.35.0
 )
 
 require (
-	github.com/anthropics/anthropic-sdk-go v1.22.1 // indirect
 	github.com/go-resty/resty/v2 v2.17.1 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
 	github.com/google/uuid v1.6.0 // indirect
-	github.com/openai/openai-go v1.12.0 // indirect
 	github.com/tidwall/gjson v1.18.0 // indirect
 	github.com/tidwall/match v1.2.0 // indirect
 	github.com/tidwall/pretty v1.2.1 // indirect