feat: 品牌重命名 Sub2API -> TianShuAPI

- 前端: 所有界面显示、i18n 文本、组件中的品牌名称
- 后端: 服务层、设置默认值、邮件模板、安装向导
- 数据库: 迁移脚本注释
- 保持功能完全一致，仅更改品牌名称

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

backend/internal/web/embed_off.go

@@ -1,20 +1,20 @@
-//go:build !embed
-
-package web
-
-import (
-	"net/http"
-
-	"github.com/gin-gonic/gin"
-)
-
-func ServeEmbeddedFrontend() gin.HandlerFunc {
-	return func(c *gin.Context) {
-		c.String(http.StatusNotFound, "Frontend not embedded. Build with -tags embed to include frontend.")
-		c.Abort()
-	}
-}
-
-func HasEmbeddedFrontend() bool {
-	return false
-}
+//go:build !embed
+
+package web
+
+import (
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+)
+
+func ServeEmbeddedFrontend() gin.HandlerFunc {
+	return func(c *gin.Context) {
+		c.String(http.StatusNotFound, "Frontend not embedded. Build with -tags embed to include frontend.")
+		c.Abort()
+	}
+}
+
+func HasEmbeddedFrontend() bool {
+	return false
+}

backend/internal/web/embed_on.go

@@ -1,78 +1,78 @@
-//go:build embed
-
-package web
-
-import (
-	"embed"
-	"io"
-	"io/fs"
-	"net/http"
-	"strings"
-
-	"github.com/gin-gonic/gin"
-)
-
-//go:embed all:dist
-var frontendFS embed.FS
-
-func ServeEmbeddedFrontend() gin.HandlerFunc {
-	distFS, err := fs.Sub(frontendFS, "dist")
-	if err != nil {
-		panic("failed to get dist subdirectory: " + err.Error())
-	}
-	fileServer := http.FileServer(http.FS(distFS))
-
-	return func(c *gin.Context) {
-		path := c.Request.URL.Path
-
-		if strings.HasPrefix(path, "/api/") ||
-			strings.HasPrefix(path, "/v1/") ||
-			strings.HasPrefix(path, "/v1beta/") ||
-			strings.HasPrefix(path, "/antigravity/") ||
-			strings.HasPrefix(path, "/setup/") ||
-			path == "/health" ||
-			path == "/responses" {
-			c.Next()
-			return
-		}
-
-		cleanPath := strings.TrimPrefix(path, "/")
-		if cleanPath == "" {
-			cleanPath = "index.html"
-		}
-
-		if file, err := distFS.Open(cleanPath); err == nil {
-			_ = file.Close()
-			fileServer.ServeHTTP(c.Writer, c.Request)
-			c.Abort()
-			return
-		}
-
-		serveIndexHTML(c, distFS)
-	}
-}
-
-func serveIndexHTML(c *gin.Context, fsys fs.FS) {
-	file, err := fsys.Open("index.html")
-	if err != nil {
-		c.String(http.StatusNotFound, "Frontend not found")
-		c.Abort()
-		return
-	}
-	defer func() { _ = file.Close() }()
-
-	content, err := io.ReadAll(file)
-	if err != nil {
-		c.String(http.StatusInternalServerError, "Failed to read index.html")
-		c.Abort()
-		return
-	}
-
-	c.Data(http.StatusOK, "text/html; charset=utf-8", content)
-	c.Abort()
-}
-
-func HasEmbeddedFrontend() bool {
-	_, err := frontendFS.ReadFile("dist/index.html")
-	return err == nil
-}
+//go:build embed
+
+package web
+
+import (
+	"embed"
+	"io"
+	"io/fs"
+	"net/http"
+	"strings"
+
+	"github.com/gin-gonic/gin"
+)
+
+//go:embed all:dist
+var frontendFS embed.FS
+
+func ServeEmbeddedFrontend() gin.HandlerFunc {
+	distFS, err := fs.Sub(frontendFS, "dist")
+	if err != nil {
+		panic("failed to get dist subdirectory: " + err.Error())
+	}
+	fileServer := http.FileServer(http.FS(distFS))
+
+	return func(c *gin.Context) {
+		path := c.Request.URL.Path
+
+		if strings.HasPrefix(path, "/api/") ||
+			strings.HasPrefix(path, "/v1/") ||
+			strings.HasPrefix(path, "/v1beta/") ||
+			strings.HasPrefix(path, "/antigravity/") ||
+			strings.HasPrefix(path, "/setup/") ||
+			path == "/health" ||
+			path == "/responses" {
+			c.Next()
+			return
+		}
+
+		cleanPath := strings.TrimPrefix(path, "/")
+		if cleanPath == "" {
+			cleanPath = "index.html"
+		}
+
+		if file, err := distFS.Open(cleanPath); err == nil {
+			_ = file.Close()
+			fileServer.ServeHTTP(c.Writer, c.Request)
+			c.Abort()
+			return
+		}
+
+		serveIndexHTML(c, distFS)
+	}
+}
+
+func serveIndexHTML(c *gin.Context, fsys fs.FS) {
+	file, err := fsys.Open("index.html")
+	if err != nil {
+		c.String(http.StatusNotFound, "Frontend not found")
+		c.Abort()
+		return
+	}
+	defer func() { _ = file.Close() }()
+
+	content, err := io.ReadAll(file)
+	if err != nil {
+		c.String(http.StatusInternalServerError, "Failed to read index.html")
+		c.Abort()
+		return
+	}
+
+	c.Data(http.StatusOK, "text/html; charset=utf-8", content)
+	c.Abort()
+}
+
+func HasEmbeddedFrontend() bool {
+	_, err := frontendFS.ReadFile("dist/index.html")
+	return err == nil
+}