Add spring-boot-microservices-project: config server, Eureka, gateway and three services on Boot 4.1.1 + Spring Cloud 2025.1.3

Product, order and inventory services behind Spring Cloud Gateway (WebMVC), configuration from a Config Server,
discovery with Eureka, a Resilience4j circuit breaker on order -> inventory and Brave tracing. Run as six plain jars;
output/ holds real transcripts (config, registry, requests, trace propagation, circuit breaker, startup race and the
load-balanced RestClient.Builder trap). Dockerfile and docker-compose.yml are included but were not run.

Co-Authored-By: Claude Sonnet 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01HhW8LD8r3EigoBaCGrQZx5

config-server/src/main/java/com/ankurm/shop/config/ConfigServerApplication.java

@@ -0,0 +1,14 @@
+package com.ankurm.shop.config;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.cloud.config.server.EnableConfigServer;
+
+/** Serves the files under src/main/resources/config to every other service. Start this one first. */
+@SpringBootApplication
+@EnableConfigServer
+public class ConfigServerApplication {
+    public static void main(String[] args) {
+        SpringApplication.run(ConfigServerApplication.class, args);
+    }
+}

config-server/src/main/resources/application.yml

@@ -0,0 +1,12 @@
+spring:
+  application:
+    name: config-server
+  profiles:
+    active: native
+  cloud:
+    config:
+      server:
+        native:
+          search-locations: classpath:/config
+server:
+  port: 8888

config-server/src/main/resources/config/application.yml

@@ -0,0 +1,9 @@
+# Served to EVERY service that asks the config server (the "application" file is the shared default).
+management:
+  endpoints:
+    web:
+      exposure:
+        include: health,info,circuitbreakers
+  tracing:
+    sampling:
+      probability: 1.0

config-server/src/main/resources/config/gateway.yml

@@ -0,0 +1,25 @@
+# Routes live here, not in the gateway jar: change a route, restart the gateway, no rebuild.
+spring:
+  cloud:
+    gateway:
+      server:
+        webmvc:
+          routes:
+            - id: products
+              uri: lb://product-service
+              predicates:
+                - Path=/api/products/**
+              filters:
+                - StripPrefix=1
+            - id: orders
+              uri: lb://order-service
+              predicates:
+                - Path=/api/orders/**
+              filters:
+                - StripPrefix=1
+            - id: inventory
+              uri: lb://inventory-service
+              predicates:
+                - Path=/api/inventory/**
+              filters:
+                - StripPrefix=1

config-server/src/main/resources/config/inventory-service.yml

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+shop:
+  inventory:
+    low-stock-threshold: 5

config-server/src/main/resources/config/order-service.yml

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+shop:
+  order:
+    currency: EUR
+    max-quantity: 10