feat: centralize utility functions, abstract SSE stream collection, and add concurrency to admin account testing.

internal/deepseek/client.go

@@ -16,10 +16,14 @@ import (
 	"ds2api/internal/auth"
 	"ds2api/internal/config"
 	trans "ds2api/internal/deepseek/transport"
+	"ds2api/internal/util"
 
 	"github.com/andybalholm/brotli"
 )
 
+// intFrom is a package-internal alias for the shared util version.
+var intFrom = util.IntFrom
+
 type Client struct {
 	Store      *config.Store
 	Auth       *auth.Resolver
@@ -288,19 +292,6 @@ func isTokenInvalid(status int, code int, msg string) bool {
 	return strings.Contains(msg, "token") || strings.Contains(msg, "unauthorized")
 }
 
-func intFrom(v any) int {
-	switch n := v.(type) {
-	case float64:
-		return int(n)
-	case int:
-		return n
-	case int64:
-		return int(n)
-	default:
-		return 0
-	}
-}
-
 func readResponseBody(resp *http.Response) ([]byte, error) {
 	encoding := strings.ToLower(strings.TrimSpace(resp.Header.Get("Content-Encoding")))
 	var reader io.Reader = resp.Body