feat: enhance agent management and validation logic

- Updated AGENTS.md to clarify agent account restrictions and permissions.
- Implemented checks in AgentNodeAdminUserStoreController and AgentNodeRoleStoreController to restrict admin user and role creation to the agent's own node.
- Enhanced validation in AdminPlayerStoreController and AdminPlayerUpdateController to enforce credit limit and rebate rate rules based on player funding mode.
- Refactored various request classes to utilize shared admin account field rules for consistency.
- Improved error handling in services related to credit allocation and rebate limits to ensure proper validation and messaging.

app/Models/AdminUser.php

@@ -430,6 +430,11 @@ final class AdminUser extends Authenticatable
 
         $codes = array_keys($merged);
 
+        // 平台账号（站点管理员等）不按线路内 AgentProfile 收紧；该过滤器仅作用于绑定代理节点的主账号。
+        if (! $this->hasPrimaryAgentBinding()) {
+            return $codes;
+        }
+
         return AgentProfileCapabilityFilter::applyToMenuActionCodes(
             $codes,
             $this->primaryAgentProfile(),