feat: support openapi chat with non-stream

[junwen-lee]

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[codecov-commenter]

Codecov Report

❌ Patch coverage is 4.65909% with 1678 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
backend/api/model/conversation/message/message.go	0.00%	840 Missing ⚠️
backend/api/model/conversation/run/run.go	0.00%	326 Missing ⚠️
...pi/model/conversation/agentrun/agentrun_service.go	0.00%	199 Missing ⚠️
.../api/model/conversation/message/message_service.go	0.00%	199 Missing ⚠️
...kend/application/conversation/openapi_agent_run.go	53.59%	66 Missing and 5 partials ⚠️
backend/api/handler/coze/agent_run_service.go	0.00%	19 Missing ⚠️
backend/api/handler/coze/message_service.go	0.00%	12 Missing ⚠️
backend/api/router/coze/middleware.go	0.00%	8 Missing ⚠️
backend/api/router/coze/api.go	0.00%	4 Missing ⚠️

Files with missing lines	Coverage Δ
backend/api/middleware/openapi_auth.go	0.00% <ø> (ø)
backend/api/router/coze/api.go	0.00% <0.00%> (ø)
backend/api/router/coze/middleware.go	0.00% <0.00%> (ø)
backend/api/handler/coze/message_service.go	8.43% <0.00%> (-1.43%)	⬇️
backend/api/handler/coze/agent_run_service.go	0.00% <0.00%> (ø)
...kend/application/conversation/openapi_agent_run.go	54.43% <53.59%> (-3.39%)	⬇️
...pi/model/conversation/agentrun/agentrun_service.go	0.00% <0.00%> (ø)
.../api/model/conversation/message/message_service.go	0.00% <0.00%> (ø)
backend/api/model/conversation/run/run.go	0.15% <0.00%> (-0.01%)	⬇️
backend/api/model/conversation/message/message.go	0.00% <0.00%> (ø)

... and 3 files with indirect coverage changes

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