Merge upstream/master into develop

Sync upstream changes from perfect-panel/server

  Includes updates from v1.0.1 to v1.2.5:
  - Currency configuration support
  - Subscribe improvements (short token, inventory check, etc.)
  - Node management enhancements
  - Database migrations
  - Bug fixes and optimizations

internal/config/config.go

@@ -29,6 +29,7 @@ type Config struct {
 	Invite        InviteConfig    `yaml:"Invite"`
 	Telegram      Telegram        `yaml:"Telegram"`
 	Log           Log             `yaml:"Log"`
+	Currency      Currency        `yaml:"Currency"`
 	Administrator struct {
 		Email    string `yaml:"Email" default:"admin@ppanel.dev"`
 		Password string `yaml:"Password" default:"password"`
@@ -241,3 +242,9 @@ type NodeDBConfig struct {
 	Block                  string
 	Outbound               string
 }
+
+type Currency struct {
+	Unit      string `yaml:"Unit" default:"CNY"`
+	Symbol    string `yaml:"Symbol" default:"USD"`
+	AccessKey string `yaml:"AccessKey" default:""`
+}