feat: LLM多阶段交互式Schema生成 + UI布局优化

- AI Service: 多阶段对话模型(理解→澄清→生成→校验→确认)，支持对话历史和当前Schema上下文
- Backend: 适配多阶段AI模型，Gateway/Service/Controller传递history和currentSchema
- Frontend: AiDesignerChat组件重写，支持阶段徽章、快速回复、Schema校验展示
- Frontend: 表单/流程设计器布局优化，AI助手和Schema预览作为独立列
- Frontend: 流程设计器元数据和模式选择器合并为一行
- Keycloak: 自定义登录主题(中文化)
- 修复CSS媒体查询括号平衡问题

ai-service/app/main.py

@@ -1,13 +1,14 @@
 from fastapi import Depends, FastAPI, HTTPException
 
 from app.config import get_settings
-from app.models import LeaveDraftSuggestionRequest, LeaveDraftSuggestionResponse, LeaveProgressAnswerRequest, LeaveProgressAnswerResponse
+from app.models import LeaveDraftSuggestionRequest, LeaveDraftSuggestionResponse, LeaveProgressAnswerRequest, LeaveProgressAnswerResponse, DesignerSuggestionRequest, DesignerSuggestionResponse
 from app.qwen import (
     QwenConfigurationError,
     QwenSuggestionGateway,
     QwenUpstreamError,
     SuggestionGateway,
     ProgressGateway,
+    DesignerGateway,
 )
 
 app = FastAPI(title="AIOA AI Service", version="0.1.0")
@@ -21,6 +22,10 @@ def get_progress_gateway() -> ProgressGateway:
     return QwenSuggestionGateway(get_settings())
 
 
+def get_designer_gateway() -> DesignerGateway:
+    return QwenSuggestionGateway(get_settings())
+
+
 @app.get("/health")
 async def health() -> dict[str, str]:
     return {"status": "UP"}
@@ -55,3 +60,20 @@ async def answer_leave_progress(
     except QwenUpstreamError as exc:
         raise HTTPException(status_code=502, detail=str(exc)) from exc
     return LeaveProgressAnswerResponse(answer=answer, model=get_settings().qwen_model)
+
+
+@app.post("/v1/designer/suggest", response_model=DesignerSuggestionResponse)
+async def suggest_design(
+    request: DesignerSuggestionRequest,
+    gateway: DesignerGateway = Depends(get_designer_gateway),
+) -> DesignerSuggestionResponse:
+    try:
+        suggestion = await gateway.suggest_design(request)
+    except QwenConfigurationError as exc:
+        raise HTTPException(status_code=503, detail=str(exc)) from exc
+    except QwenUpstreamError as exc:
+        raise HTTPException(status_code=502, detail=str(exc)) from exc
+    return DesignerSuggestionResponse(
+        suggestion=suggestion,
+        model=get_settings().qwen_model,
+    )