Enhance user plan management and update related endpoints

- Added new configuration options for user plans in `.env.example`, including `Plans__MaxCustomConfigCount` and `Plans__MinCustomConfigCount`.
- Introduced `MapPlanEndpoints` in `Program.cs` to handle plan-related API routes.
- Implemented `SetUserPlan` endpoint in `RoleEndpoints` to allow admins to assign plans to users.
- Removed deprecated role request approval endpoints from `AdminSupportEndpoints`.
- Updated `ITelegramNotifier` and related classes to reflect changes in role request handling and payment notifications.
- Refactored role management commands to remove `MaxConfigs` and focus on `MaxIpLimit` and billing settings.
- Enhanced billing request handling to accommodate plan changes instead of role changes.
- Updated various interfaces and command handlers to support new plan management features.

backend/tests/PnvPanel.Domain.Tests/Billing/PlanChangeTopUpTests.cs

@@ -4,17 +4,17 @@ using Xunit;
 
 namespace PnvPanel.Domain.Tests.Billing;
 
-public class RoleChangeTopUpTests
+public class PlanChangeTopUpTests
 {
     private static readonly DateTimeOffset Now = new(2026, 1, 1, 0, 0, 0, TimeSpan.Zero);
 
     [Fact]
-    public void Compute_WhenNewRoleCheaper_ReturnsNull()
+    public void Compute_WhenNewPlanCheaper_ReturnsNull()
     {
-        var amount = RoleChangeTopUp.Compute(
+        var amount = PlanChangeTopUp.Compute(
             pricePerConfigPerMonth: 200,
-            oldMaxConfigs: 10,
-            newMaxConfigs: 3,
+            oldConfigCount: 10,
+            newConfigCount: 3,
             discountTiers: [],
             paidUntil: Now.AddDays(30),
             now: Now
@@ -26,10 +26,10 @@ public class RoleChangeTopUpTests
     [Fact]
     public void Compute_WhenPaidUntilAlreadyExpired_ReturnsNull()
     {
-        var amount = RoleChangeTopUp.Compute(
+        var amount = PlanChangeTopUp.Compute(
             pricePerConfigPerMonth: 200,
-            oldMaxConfigs: 3,
-            newMaxConfigs: 10,
+            oldConfigCount: 3,
+            newConfigCount: 10,
             discountTiers: [],
             paidUntil: Now.AddDays(-1),
             now: Now
@@ -39,12 +39,12 @@ public class RoleChangeTopUpTests
     }
 
     [Fact]
-    public void Compute_WhenEitherRoleUnlimited_ReturnsNull()
+    public void Compute_WhenEitherCountUnlimited_ReturnsNull()
     {
-        var amount = RoleChangeTopUp.Compute(
+        var amount = PlanChangeTopUp.Compute(
             pricePerConfigPerMonth: 200,
-            oldMaxConfigs: 3,
-            newMaxConfigs: -1,
+            oldConfigCount: 3,
+            newConfigCount: -1,
             discountTiers: [],
             paidUntil: Now.AddDays(30),
             now: Now
@@ -56,12 +56,12 @@ public class RoleChangeTopUpTests
     [Fact]
     public void Compute_WhenUpgrading_ReturnsProratedDifference()
     {
-        // Старая роль: 200 * 3 = 600 ₽/мес. Новая: 200 * 10 = 2000 ₽/мес. Разница 1400 ₽/мес,
+        // Старый тариф: 200 * 3 = 600 ₽/мес. Новый: 200 * 10 = 2000 ₽/мес. Разница 1400 ₽/мес,
         // за 30 дней (ровно месяц) — 1400 ₽.
-        var amount = RoleChangeTopUp.Compute(
+        var amount = PlanChangeTopUp.Compute(
             pricePerConfigPerMonth: 200,
-            oldMaxConfigs: 3,
-            newMaxConfigs: 10,
+            oldConfigCount: 3,
+            newConfigCount: 10,
             discountTiers: [],
             paidUntil: Now.AddDays(30),
             now: Now
@@ -74,10 +74,10 @@ public class RoleChangeTopUpTests
     public void Compute_ProratesToRemainingDaysOnly()
     {
         // Та же разница 1400 ₽/мес, но остаётся только 15 из 30 дней — половина.
-        var amount = RoleChangeTopUp.Compute(
+        var amount = PlanChangeTopUp.Compute(
             pricePerConfigPerMonth: 200,
-            oldMaxConfigs: 3,
-            newMaxConfigs: 10,
+            oldConfigCount: 3,
+            newConfigCount: 10,
             discountTiers: [],
             paidUntil: Now.AddDays(15),
             now: Now
@@ -87,16 +87,16 @@ public class RoleChangeTopUpTests
     }
 
     [Fact]
-    public void Compute_AppliesDiscountTiersToBothRoles()
+    public void Compute_AppliesDiscountTiersToBothCounts()
     {
         var tiers = new[] { PricingDiscountTier.Create(Guid.NewGuid(), minConfigs: 10, discountPercent: 10) };
 
-        // Старая роль (3 конфига, без скидки): 200*3 = 600. Новая (10 конфигов, порог скидки достигнут):
+        // Старый тариф (3 конфига, без скидки): 200*3 = 600. Новый (10 конфигов, порог скидки достигнут):
         // 200*10 = 2000, -10% = 1800. Разница 1200 ₽/мес, за 30 дней — 1200 ₽.
-        var amount = RoleChangeTopUp.Compute(
+        var amount = PlanChangeTopUp.Compute(
             pricePerConfigPerMonth: 200,
-            oldMaxConfigs: 3,
-            newMaxConfigs: 10,
+            oldConfigCount: 3,
+            newConfigCount: 10,
             discountTiers: tiers,
             paidUntil: Now.AddDays(30),
             now: Now