feat(inference): 实现文生图与图片编辑 API 调用，新增管线与编辑 HTTP 端点，JWT 认证中间件

- inference.go: GenerateImages 改为 API 优先（callImageGenAPI），无 key 回退 mock；新增 EditImages/callImageEditAPI（multipart 上传编辑）；提取 parseImageResponse 共享响应解析
- handler/generate.go: POST /api/v1/generate 触发生成管线，返回 base64 图片
- handler/edit.go: POST /api/v1/images/edit 图片编辑端点
- mildware/auth.go: JWT Bearer token 认证中间件
- main.go: 路由拆分公开/认证组，generate 与 images/edit 需鉴权

backend/internal/handler/edit.go

@@ -0,0 +1,59 @@
+package handler
+
+import (
+	"encoding/base64"
+	"net/http"
+
+	"gen2d/internal/model"
+	"gen2d/internal/service"
+
+	"github.com/gin-gonic/gin"
+)
+
+// EditImageRequest 图片编辑请求。
+type EditImageRequest struct {
+	Image  string `json:"image" binding:"required"`  // 底图 base64 编码
+	Prompt string `json:"prompt" binding:"required"`  // 编辑指令
+	Count  int    `json:"count"`                      // 生成数量，默认 1
+}
+
+// EditImageResponse 图片编辑响应体。
+type EditImageResponse struct {
+	Assets []AssetResponse `json:"assets"`
+}
+
+// EditImage 图片编辑接口，基于已有图片和文本指令生成修改后的图片。
+func EditImage(c *gin.Context) {
+	var req EditImageRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		c.JSON(http.StatusBadRequest, model.Fail(http.StatusBadRequest, "参数错误: "+err.Error()))
+		return
+	}
+
+	imageData, err := base64.StdEncoding.DecodeString(req.Image)
+	if err != nil {
+		c.JSON(http.StatusBadRequest, model.Fail(http.StatusBadRequest, "图片 base64 解码失败: "+err.Error()))
+		return
+	}
+
+	count := req.Count
+	if count <= 0 {
+		count = 1
+	}
+
+	images, err := service.EditImages(c.Request.Context(), imageData, req.Prompt, count)
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, model.Fail(http.StatusInternalServerError, "图片编辑失败: "+err.Error()))
+		return
+	}
+
+	assets := make([]AssetResponse, len(images))
+	for i, img := range images {
+		assets[i] = AssetResponse{
+			Data:   base64.StdEncoding.EncodeToString(img.Data),
+			Format: img.Format,
+		}
+	}
+
+	c.JSON(http.StatusOK, model.OK(EditImageResponse{Assets: assets}))
+}

backend/internal/handler/generate.go

@@ -0,0 +1,84 @@
+package handler
+
+import (
+	"encoding/base64"
+	"net/http"
+
+	"gen2d/internal/model"
+	"gen2d/internal/service"
+
+	"github.com/gin-gonic/gin"
+)
+
+// GenerateRequest 素材生成请求。
+type GenerateRequest struct {
+	Prompt       string            `json:"prompt"`
+	AssetType    string            `json:"assetType" binding:"required"`
+	Tags         []string          `json:"tags"`
+	UserNote     string            `json:"userNote"`
+	ProjectStyle map[string]string `json:"projectStyle"`
+	TaskStyle    map[string]string `json:"taskStyle"`
+	Resolution   int               `json:"resolution"`
+	Directions   int               `json:"directions"`
+	FramesPerDir int               `json:"framesPerDir"`
+	Format       string            `json:"format"`
+}
+
+// GenerateResponse 素材生成响应体。
+type GenerateResponse struct {
+	Assets   []AssetResponse        `json:"assets"`
+	Metadata service.AssetMetadata  `json:"metadata"`
+}
+
+// AssetResponse 单个素材响应（二进制 Data 转 base64）。
+type AssetResponse struct {
+	Data   string `json:"data"`
+	Format string `json:"format"`
+	URL    string `json:"url"`
+}
+
+// Generate 素材生成接口，调用完整生成管线（PromptOptimizer → AssetGenerator → QualitySupervisor → FormatAdapter）。
+func Generate(c *gin.Context) {
+	var req GenerateRequest
+	if err := c.ShouldBindJSON(&req); err != nil {
+		c.JSON(http.StatusBadRequest, model.Fail(http.StatusBadRequest, "参数错误: "+err.Error()))
+		return
+	}
+
+	in := service.PipelineInput{
+		Prompt:       req.Prompt,
+		AssetType:    req.AssetType,
+		Tags:         req.Tags,
+		UserNote:     req.UserNote,
+		ProjectStyle: req.ProjectStyle,
+		TaskStyle:    req.TaskStyle,
+		Params: service.AssetParams{
+			Resolution: req.Resolution,
+			Frames: service.FrameParams{
+				Directions:        req.Directions,
+				FramesPerDirection: req.FramesPerDir,
+			},
+			Format: req.Format,
+		},
+	}
+
+	output, err := service.RunPipeline(c.Request.Context(), in)
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, model.Fail(http.StatusInternalServerError, "素材生成失败: "+err.Error()))
+		return
+	}
+
+	assets := make([]AssetResponse, len(output.Assets))
+	for i, a := range output.Assets {
+		assets[i] = AssetResponse{
+			Data:   base64.StdEncoding.EncodeToString(a.Data),
+			Format: a.Format,
+			URL:    a.URL,
+		}
+	}
+
+	c.JSON(http.StatusOK, model.OK(GenerateResponse{
+		Assets:   assets,
+		Metadata: output.Metadata,
+	}))
+}