feat(protocol): 可美 KM Seedream - 接入图片生成与编辑

backend/internal/app/model_capability_defaults.go

@@ -27,6 +27,19 @@ func DefaultImageCapabilityConfig(protocol string, modelName string) *ImageCapab
 		MaxOutputs:            15,
 	}
 	switch model.ChannelInterfaceType(protocol) {
+	case "km-kemei-seedream":
+		image.References.MaxImages = 10
+		image.References.MaskSupported = false
+		presets := kemeiSeedreamImagePresets()
+		values := make([]string, 0, len(presets))
+		for _, preset := range presets {
+			values = append(values, preset.Size)
+		}
+		image.Size = ImageSizeConfig{Parameter: "size", Values: values, Default: "2048x2048", AllowCustom: true, Presets: presets}
+		image.Quality = ImageQualityConfig{Supported: false, Values: []string{}, Default: "auto"}
+		// 透明背景需要带 alpha 的单张参考图，通过插件命名空间显式配置。
+		image.TransparentBackground = VideoBooleanConfig{Supported: false, Default: false}
+		image.MaxOutputs = 1
 	case model.ChannelInterfaceGrokImage:
 		image.References.MaxImages = 1
 		image.References.MaskSupported = false

backend/internal/app/model_capability_kemei.go

@@ -0,0 +1,29 @@
+package app
+
+import (
+	"strconv"
+	"strings"
+)
+
+// 供应商与 Seedream 5.0 官方文档的精确尺寸；档位不能由通用像素阈值推断。
+func kemeiSeedreamImagePresets() []ImageSizePreset {
+	ratios := []string{"1:1", "4:3", "3:4", "16:9", "9:16", "3:2", "2:3", "21:9"}
+	tiers := []struct {
+		name  string
+		sizes []string
+	}{
+		{"1k", []string{"1024x1024", "1152x864", "864x1152", "1424x800", "800x1424", "1248x832", "832x1248", "1568x672"}},
+		{"1.5k", []string{"1536x1536", "1792x1344", "1344x1792", "2048x1152", "1152x2048", "1872x1248", "1248x1872", "2352x1008"}},
+		{"2k", []string{"2048x2048", "2368x1776", "1776x2368", "2816x1584", "1584x2816", "2496x1664", "1664x2496", "3136x1344"}},
+	}
+	result := make([]ImageSizePreset, 0, 24)
+	for _, tier := range tiers {
+		for index, size := range tier.sizes {
+			parts := strings.Split(size, "x")
+			width, _ := strconv.Atoi(parts[0])
+			height, _ := strconv.Atoi(parts[1])
+			result = append(result, ImageSizePreset{Tier: tier.name, Ratio: ratios[index], Width: width, Height: height, Size: size})
+		}
+	}
+	return result
+}

backend/internal/app/model_capability_kemei_test.go

@@ -0,0 +1,23 @@
+package app
+
+import "testing"
+
+func TestKemeiSeedreamDefaultsAreValidAndUseOfficialTiers(t *testing.T) {
+	for _, name := range []string{"doubao-seedream-5-0-pro-260628", "doubao-seedream-5-0-flash-260915"} {
+		profile := DefaultModelCapabilityConfigForModel("km-kemei-seedream", name).Image
+		if err := validateImageCapabilityConfig(profile); err != nil {
+			t.Fatal(err)
+		}
+		if profile.References.MaxImages != 10 || profile.References.MaskSupported || profile.MaxOutputs != 1 || profile.Size.Default != "2048x2048" || len(profile.Size.Presets) != 24 || profile.Quality.Supported || profile.TransparentBackground.Supported {
+			t.Fatalf("defaults: %#v", profile)
+		}
+		for _, preset := range profile.Size.Presets {
+			if preset.Tier == "4k" {
+				t.Fatal("unsupported 4K default")
+			}
+			if preset.Size == "2816x1584" && preset.Tier != "2k" {
+				t.Fatal("official 2K must not become 4K")
+			}
+		}
+	}
+}

backend/internal/app/model_capability_validate.go

@@ -65,8 +65,8 @@ func validateImageCapabilityConfig(value *ImageCapabilityConfig) error {
 	}
 	seenPresets := make(map[string]bool)
 	for _, preset := range value.Size.Presets {
-		if preset.Tier != "1k" && preset.Tier != "2k" && preset.Tier != "4k" {
-			return BadAuthRequest("图片分辨率档位仅支持 1K、2K、4K")
+		if preset.Tier != "1k" && preset.Tier != "1.5k" && preset.Tier != "2k" && preset.Tier != "4k" {
+			return BadAuthRequest("图片分辨率档位仅支持 1K、1.5K、2K、4K")
 		}
 		parts := strings.Split(preset.Ratio, ":")
 		if len(parts) != 2 {
@@ -416,6 +416,8 @@ func imageResolutionTier(quality string) string {
 	switch strings.ToLower(strings.TrimSpace(quality)) {
 	case "1k", "low":
 		return "1k"
+	case "1.5k":
+		return "1.5k"
 	case "2k", "medium":
 		return "2k"
 	case "4k", "high":