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/Services/Agent/CreditAllocationValidator.php

@@ -13,13 +13,47 @@ final class CreditAllocationValidator
         private readonly AgentCreditAllocatedSyncService $allocatedSync,
     ) {}
 
+    public function assertChildCreditLimitWithinParent(
+        AgentNode $parent,
+        int $previousChildLimit,
+        int $newChildLimit,
+        bool $isNewChild,
+    ): void {
+        if ($newChildLimit < 0) {
+            throw ValidationException::withMessages([
+                'credit_limit' => ['invalid'],
+            ]);
+        }
+
+        $this->allocatedSync->syncForAgent($parent);
+
+        $profile = AgentProfile::query()->where('agent_node_id', $parent->id)->first();
+        if ($profile === null) {
+            throw ValidationException::withMessages([
+                'credit_limit' => ['parent_profile_required'],
+            ]);
+        }
+
+        $available = max(0, (int) $profile->credit_limit - (int) $profile->allocated_credit);
+        $floor = $isNewChild ? 0 : max(0, $previousChildLimit);
+        $maxAllowed = $floor + $available;
+
+        if ($newChildLimit > $maxAllowed) {
+            throw ValidationException::withMessages([
+                'credit_limit' => ['exceeds_available'],
+            ]);
+        }
+    }
+
     public function assertAllocationWithinParent(AgentNode $parent, int $additionalCredit): void
     {
         $this->allocatedSync->syncForAgent($parent);
 
         $profile = AgentProfile::query()->where('agent_node_id', $parent->id)->first();
         if ($profile === null) {
-            return;
+            throw ValidationException::withMessages([
+                'credit_limit' => ['parent_profile_required'],
+            ]);
         }
 
         $available = max(0, (int) $profile->credit_limit - (int) $profile->allocated_credit);