Change JobGateway port from 8080 to 8086 for standardization

Updated JobGateway port from 8080 to 8086 across all configuration files, test files, and exercise solutions to standardize the port for the JobGateway service.

Changes:
- JobGateway launchSettings.json: applicationUrl changed to 8086
- JobGateway appsettings.json: BaseUrl changed to 8086
- AppHost configuration: WithHttpEndpoint port changed to 8086
- All test files and exercise solutions updated to use 8086
- Comments and documentation updated to reflect new port

Co-authored-by: devstress <[email protected]>

Author: Copilot

FlinkDotNet/FlinkDotNet.JobGateway/Properties/launchSettings.json

@@ -6,7 +6,7 @@
       "environmentVariables": {
         "ASPNETCORE_ENVIRONMENT": "Development"
       },
-      "applicationUrl": "http://localhost:8080"
+      "applicationUrl": "http://localhost:8086"
     }
   }
 }

FlinkDotNet/FlinkDotNet.JobGateway/appsettings.json

@@ -16,7 +16,7 @@
     }
   },
   "FlinkJobGateway": {
-    "BaseUrl": "http://localhost:8080/",
+    "BaseUrl": "http://localhost:8086/",
     "HttpTimeout": "00:05:00",
     "MaxRetries": 3,
     "RetryDelay": "00:00:01",

LearningCourse/Day01-Kafka-Flink-Data-Pipeline/Exercise-Solutions/Exercise1-StringCapitalize/Program.cs

@@ -39,7 +39,7 @@ static class Program
             Environment.GetEnvironmentVariable("KAFKA_FLINK_BOOTSTRAP_SERVERS") ?? "kafka:9092";
 
         private static string FlinkGatewayUrl =>
-            Environment.GetEnvironmentVariable("FLINK_JOB_GATEWAY_URL") ?? "http://localhost:8080";
+            Environment.GetEnvironmentVariable("FLINK_JOB_GATEWAY_URL") ?? "http://localhost:8086";
 
         private static string FlinkJobManagerUrl =>
             Environment.GetEnvironmentVariable("FLINK_JOBMANAGER_URL") ?? "http://localhost:8081";

LearningCourse/Day01-Kafka-Flink-Data-Pipeline/Exercise-Solutions/Exercise2-BackupAggregator/Program.cs

@@ -32,7 +32,7 @@ static class Program
         // Flink Gateway configuration
         // Lazy evaluation - reads env var when first accessed, not at class load time
         private static string FlinkGatewayUrl =>
-            Environment.GetEnvironmentVariable("FLINK_JOB_GATEWAY_URL") ?? "http://localhost:8080";
+            Environment.GetEnvironmentVariable("FLINK_JOB_GATEWAY_URL") ?? "http://localhost:8086";
 
         private static string FlinkJobManagerUrl =>
             Environment.GetEnvironmentVariable("FLINK_JOBMANAGER_URL") ?? "http://localhost:8081";

LearningCourse/Day03-AI-Stream-Processing/Exercise-Solutions/Exercise31/Program.cs

@@ -26,7 +26,7 @@ class Program
         Environment.GetEnvironmentVariable("KAFKA_FLINK_BOOTSTRAP_SERVERS") ?? "kafka:9092";
 
     private static string FlinkGatewayUrl =>
-        Environment.GetEnvironmentVariable("FLINK_JOB_GATEWAY_URL") ?? "http://localhost:8080";
+        Environment.GetEnvironmentVariable("FLINK_JOB_GATEWAY_URL") ?? "http://localhost:8086";
 
     private const string RegistrationTopic = "ai-model-registrations";
     private const string ValidationTopic = "ai-model-validations";

LearningCourse/Day03-AI-Stream-Processing/Exercise-Solutions/Exercise32/Program.cs

@@ -29,7 +29,7 @@ public class Program
         Environment.GetEnvironmentVariable("KAFKA_FLINK_BOOTSTRAP_SERVERS") ?? "kafka:9092";
 
     private static string FlinkGatewayUrl =>
-        Environment.GetEnvironmentVariable("FLINK_JOB_GATEWAY_URL") ?? "http://localhost:8080";
+        Environment.GetEnvironmentVariable("FLINK_JOB_GATEWAY_URL") ?? "http://localhost:8086";
 
     public static async Task Main(string[] args)
     {

LearningCourse/Day03-AI-Stream-Processing/Exercise-Solutions/Exercise33/Program.cs

@@ -33,7 +33,7 @@ class Program
         Environment.GetEnvironmentVariable("KAFKA_FLINK_BOOTSTRAP_SERVERS") ?? "kafka:9092";
 
     private static string FlinkGatewayUrl =>
-        Environment.GetEnvironmentVariable("FLINK_JOB_GATEWAY_URL") ?? "http://localhost:8080";
+        Environment.GetEnvironmentVariable("FLINK_JOB_GATEWAY_URL") ?? "http://localhost:8086";
 
     private const string InputTopic = "fraud-transactions-input";
     private const string PredictionsTopic = "fraud-model-predictions";

LearningCourse/Day03-AI-Stream-Processing/Exercise-Solutions/Exercise34/Program.cs

@@ -32,7 +32,7 @@ class Program
         Environment.GetEnvironmentVariable("KAFKA_FLINK_BOOTSTRAP_SERVERS") ?? "kafka:9092";
 
     private static string FlinkGatewayUrl =>
-        Environment.GetEnvironmentVariable("FLINK_JOB_GATEWAY_URL") ?? "http://localhost:8080";
+        Environment.GetEnvironmentVariable("FLINK_JOB_GATEWAY_URL") ?? "http://localhost:8086";
 
     private const string InputTopic = "mlnet-transactions-input";
     private const string OutputTopic = "mlnet-fraud-predictions-output";

LearningCourse/Day04-Production-Backpressure/Exercise-Solutions/Exercise41/Program.cs

@@ -32,7 +32,7 @@ class Program
         Environment.GetEnvironmentVariable("KAFKA_FLINK_BOOTSTRAP_SERVERS") ?? "kafka:9092";
 
     private static string FlinkGatewayUrl =>
-        Environment.GetEnvironmentVariable("FLINK_JOB_GATEWAY_URL") ?? "http://localhost:8080";
+        Environment.GetEnvironmentVariable("FLINK_JOB_GATEWAY_URL") ?? "http://localhost:8086";
 
     private const string InputTopic = "streaming-requests-input";
     private const string OutputTopic = "streaming-sessions-output";

LearningCourse/Day04-Production-Backpressure/Exercise-Solutions/Exercise42/Program.cs

@@ -32,7 +32,7 @@ class Program
         Environment.GetEnvironmentVariable("KAFKA_FLINK_BOOTSTRAP_SERVERS") ?? "kafka:9092";
 
     private static string FlinkGatewayUrl =>
-        Environment.GetEnvironmentVariable("FLINK_JOB_GATEWAY_URL") ?? "http://localhost:8080";
+        Environment.GetEnvironmentVariable("FLINK_JOB_GATEWAY_URL") ?? "http://localhost:8086";
 
     // Kafka topics for multi-tier pipeline
     private const string ClientRequestsTopic = "client-requests-input";