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/server/middleware/recovery.go

@@ -1,64 +1,64 @@
-package middleware
-
-import (
-	"errors"
-	"net"
-	"net/http"
-	"os"
-	"strings"
-
-	infraerrors "github.com/Wei-Shaw/sub2api/internal/pkg/errors"
-	"github.com/Wei-Shaw/sub2api/internal/pkg/response"
-	"github.com/gin-gonic/gin"
-)
-
-// Recovery converts panics into the project's standard JSON error envelope.
-//
-// It preserves Gin's broken-pipe handling by not attempting to write a response
-// when the client connection is already gone.
-func Recovery() gin.HandlerFunc {
-	return gin.CustomRecoveryWithWriter(gin.DefaultErrorWriter, func(c *gin.Context, recovered any) {
-		recoveredErr, _ := recovered.(error)
-
-		if isBrokenPipe(recoveredErr) {
-			if recoveredErr != nil {
-				_ = c.Error(recoveredErr)
-			}
-			c.Abort()
-			return
-		}
-
-		if c.Writer.Written() {
-			c.Abort()
-			return
-		}
-
-		response.ErrorWithDetails(
-			c,
-			http.StatusInternalServerError,
-			infraerrors.UnknownMessage,
-			infraerrors.UnknownReason,
-			nil,
-		)
-		c.Abort()
-	})
-}
-
-func isBrokenPipe(err error) bool {
-	if err == nil {
-		return false
-	}
-
-	var opErr *net.OpError
-	if !errors.As(err, &opErr) {
-		return false
-	}
-
-	var syscallErr *os.SyscallError
-	if !errors.As(opErr.Err, &syscallErr) {
-		return false
-	}
-
-	msg := strings.ToLower(syscallErr.Error())
-	return strings.Contains(msg, "broken pipe") || strings.Contains(msg, "connection reset by peer")
-}
+package middleware
+
+import (
+	"errors"
+	"net"
+	"net/http"
+	"os"
+	"strings"
+
+	infraerrors "github.com/Wei-Shaw/sub2api/internal/pkg/errors"
+	"github.com/Wei-Shaw/sub2api/internal/pkg/response"
+	"github.com/gin-gonic/gin"
+)
+
+// Recovery converts panics into the project's standard JSON error envelope.
+//
+// It preserves Gin's broken-pipe handling by not attempting to write a response
+// when the client connection is already gone.
+func Recovery() gin.HandlerFunc {
+	return gin.CustomRecoveryWithWriter(gin.DefaultErrorWriter, func(c *gin.Context, recovered any) {
+		recoveredErr, _ := recovered.(error)
+
+		if isBrokenPipe(recoveredErr) {
+			if recoveredErr != nil {
+				_ = c.Error(recoveredErr)
+			}
+			c.Abort()
+			return
+		}
+
+		if c.Writer.Written() {
+			c.Abort()
+			return
+		}
+
+		response.ErrorWithDetails(
+			c,
+			http.StatusInternalServerError,
+			infraerrors.UnknownMessage,
+			infraerrors.UnknownReason,
+			nil,
+		)
+		c.Abort()
+	})
+}
+
+func isBrokenPipe(err error) bool {
+	if err == nil {
+		return false
+	}
+
+	var opErr *net.OpError
+	if !errors.As(err, &opErr) {
+		return false
+	}
+
+	var syscallErr *os.SyscallError
+	if !errors.As(opErr.Err, &syscallErr) {
+		return false
+	}
+
+	msg := strings.ToLower(syscallErr.Error())
+	return strings.Contains(msg, "broken pipe") || strings.Contains(msg, "connection reset by peer")
+}