Fix remaining issues from code review

- Add getSubscriptionBenefitsDirect to avoid deadlock when calling GetSubscriptionBenefits while holding usersMutex
- Fix handlers_devfund.go to use getSubscriptionBenefitsDirect
- Fix handlers_keys.go to use getSubscriptionBenefitsDirect
- Fix handlers_systems.go to update global users slice instead of local copy
- All code now compiles and builds successfully

Co-authored-by: Mistium <92952823+Mistium@users.noreply.github.com>

Author: Copilot

handlers_devfund.go

@@ -94,7 +94,7 @@ func escrowTransfer(c *gin.Context) {
 
 	// Add transaction directly while holding lock
 	txs := getObjectSlice(*fromUser, "sys.transactions")
-	benefits := fromUser.GetSubscriptionBenefits()
+	benefits := getSubscriptionBenefitsDirect(*fromUser)
 
 	tx := map[string]any{
 		"note":        note,
@@ -203,7 +203,7 @@ func escrowRelease(c *gin.Context) {
 
 	// Add transaction directly while holding lock
 	txs := getObjectSlice(*toUser, "sys.transactions")
-	benefits := toUser.GetSubscriptionBenefits()
+	benefits := getSubscriptionBenefitsDirect(*toUser)
 
 	tx := map[string]any{
 		"note":        note,

handlers_keys.go

@@ -645,7 +645,7 @@ func checkSubscriptions() {
 
 						// Add transaction directly
 						txs := getObjectSlice(users[userIndex], "sys.transactions")
-						benefits := users[userIndex].GetSubscriptionBenefits()
+						benefits := getSubscriptionBenefitsDirect(users[userIndex])
 						tx := map[string]any{
 							"note":      "key purchase",
 							"key_id":    key.Key,
@@ -669,7 +669,7 @@ func checkSubscriptions() {
 
 						// Add transaction for owner
 						ownerTxs := getObjectSlice(owner, "sys.transactions")
-						ownerBenefits := owner.GetSubscriptionBenefits()
+						ownerBenefits := getSubscriptionBenefitsDirect(owner)
 						ownerTx := map[string]any{
 							"note":      "key purchase",
 							"key_id":    key.Key,

handlers_systems.go

@@ -44,13 +44,17 @@ func renameSystem(systemName string, newName string) error {
 	system.Name = newName
 	systems[newName] = system
 
-	users, err := getAccountsBy("system", systemName, -1)
+	// Check if any users have this system before locking
+	_, err := getAccountsBy("system", systemName, -1)
 	if err != nil {
-		return nil
+		// No users found with this system, continue anyway
 	}
 	usersMutex.Lock()
+	// Iterate over global users slice and update matching users
 	for i := range users {
-		setUserKeyDirect(&users[i], "system", newName)
+		if strings.EqualFold(getStringDirect(users[i], "system"), systemName) {
+			setUserKeyDirect(&users[i], "system", newName)
+		}
 	}
 	usersMutex.Unlock()
 	go saveUsers()

types.go

@@ -348,6 +348,31 @@ func (u User) GetSubscriptionBenefits() sub_benefits {
 	return subs_benefits[strings.ToLower(tier)]
 }
 
+// getSubscriptionBenefitsDirect gets subscription benefits without acquiring mutex.
+// MUST be called while holding usersMutex or the appropriate user mutex.
+func getSubscriptionBenefitsDirect(u User) sub_benefits {
+	username := u.GetUsername()
+	if strings.EqualFold(username, "mist") {
+		return subs_benefits["max"]
+	}
+	usub := getKeyDirect(u, "sys.subscription")
+	tier := "Free"
+	
+	if usub != nil {
+		if sub, ok := usub.(map[string]any); ok {
+			tier = getStringOrDefault(sub["tier"], "Free")
+			nextBilling := int64(getIntOrDefault(sub["next_billing"], 0))
+			
+			// Check if subscription is still valid
+			if nextBilling > 0 && nextBilling < time.Now().UnixMilli() {
+				tier = "Free"
+			}
+		}
+	}
+	
+	return subs_benefits[strings.ToLower(tier)]
+}
+
 func (u User) GetBlockedIps() []string {
 	return getStringSlice(u, "blocked_ips")
 }