feat(ops): improve Dockerfile caching, add dockerignore, docker profile, Makefile help

- Server Dockerfile: add Maven dependency caching layer for faster rebuilds
- Add .dockerignore for server and web to reduce build context
- Add docker profile to application.yml for container env var mapping
- Makefile: add help, logs, db-reset targets with ## annotations

Makefile

@@ -1,63 +1,66 @@
-.PHONY: dev dev-down build test clean web-install dev-server dev-web build-web test-web typecheck-web lint-web generate-api prod-up prod-down
+.PHONY: help dev dev-down build test clean web-install dev-server dev-web build-web test-web typecheck-web lint-web generate-api prod-up prod-down logs db-reset
 
-# 启动本地开发环境（仅依赖服务）
-dev:
+help: ## 显示帮助
+	@grep -E '^[a-zA-Z_-]+:.*?## .*$$' $(MAKEFILE_LIST) | sort | \
+		awk 'BEGIN {FS = ":.*?## "}; {printf "\033[36m%-15s\033[0m %s\n", $$1, $$2}'
+
+dev: ## 启动本地开发环境（仅依赖服务）
 	docker compose up -d
 	@echo "Waiting for services to be healthy..."
 	@sleep 5
 	@echo "Services ready. Start backend with: make dev-server"
 	@echo "Start frontend with: make dev-web"
 
-dev-server:
+dev-server: ## 启动后端开发服务器
 	cd server && ./mvnw spring-boot:run -Dspring-boot.run.profiles=local
 
-# 停止本地开发环境
-dev-down:
+dev-down: ## 停止本地开发环境
 	docker compose down
 
-# 构建后端
-build:
+build: ## 构建后端
 	cd server && ./mvnw clean package -DskipTests
 
-# 运行测试
-test:
+test: ## 运行后端测试
 	cd server && ./mvnw test
 
-# 清理构建产物
-clean:
+clean: ## 清理构建产物
 	cd server && ./mvnw clean
 	docker compose down -v
 
-# 生成 OpenAPI 类型（前端用）
-generate-api:
+generate-api: ## 生成 OpenAPI 类型（前端用）
 	@echo "Generating OpenAPI types..."
 	cd web && pnpm run generate-api
 
-web-install:
+web-install: ## 安装前端依赖
 	cd web && pnpm install
 
-# 前端开发服务器
-dev-web:
+dev-web: ## 启动前端开发服务器
 	cd web && pnpm run dev
 
-# 构建前端
-build-web:
+build-web: ## 构建前端
 	cd web && pnpm run build
 
-# 前端测试
-test-web:
+test-web: ## 运行前端测试
 	cd web && pnpm run test
 
-# 前端类型检查
-typecheck-web:
+typecheck-web: ## 前端类型检查
 	cd web && pnpm run typecheck
 
-# 前端代码检查
-lint-web:
+lint-web: ## 前端代码检查
 	cd web && pnpm run lint
 
-prod-up:
+prod-up: ## 一键启动全部服务（生产模式）
 	docker compose -f docker-compose.prod.yml up -d --build
 
-prod-down:
+prod-down: ## 停止全部服务（生产模式）
 	docker compose -f docker-compose.prod.yml down
+
+logs: ## 查看后端服务日志
+	docker compose -f docker-compose.prod.yml logs -f server
+
+db-reset: ## 重置数据库
+	docker compose down -v
+	docker compose up -d postgres
+	@echo "Waiting for postgres..."
+	@sleep 3
+	cd server && ./mvnw flyway:migrate -pl skillhub-app

server/.dockerignore

@@ -0,0 +1,5 @@
+**/target/
+**/.idea/
+**/*.iml
+.git/
+*.md

server/Dockerfile

@@ -1,14 +1,34 @@
+# ---- Build Stage ----
 FROM eclipse-temurin:21-jdk-alpine AS build
 WORKDIR /app
+
+# Cache dependencies
+COPY pom.xml .
+COPY skillhub-domain/pom.xml skillhub-domain/
+COPY skillhub-auth/pom.xml skillhub-auth/
+COPY skillhub-search/pom.xml skillhub-search/
+COPY skillhub-infra/pom.xml skillhub-infra/
+COPY skillhub-storage/pom.xml skillhub-storage/
+COPY skillhub-app/pom.xml skillhub-app/
+COPY mvnw .
+COPY .mvn .mvn
+RUN ./mvnw dependency:go-offline -B
+
 COPY . .
 RUN ./mvnw package -DskipTests -B
 
+# ---- Runtime Stage ----
 FROM eclipse-temurin:21-jre-alpine
-WORKDIR /app
-COPY --from=build /app/skillhub-app/target/*.jar app.jar
 RUN addgroup -S app && adduser -S app -G app
+WORKDIR /app
+
+COPY --from=build /app/skillhub-app/target/*.jar app.jar
+
+RUN chown -R app:app /app
 USER app
+
 EXPOSE 8080
 HEALTHCHECK --interval=10s --timeout=3s \
   CMD wget -qO- http://localhost:8080/actuator/health || exit 1
+
 ENTRYPOINT ["java", "-XX:MaxRAMPercentage=75.0", "-jar", "app.jar"]

server/skillhub-app/src/main/resources/application.yml

@@ -71,3 +71,18 @@ management:
   endpoint:
     health:
       show-details: when-authorized
+
+---
+# Docker profile
+spring:
+  config:
+    activate:
+      on-profile: docker
+  datasource:
+    url: jdbc:postgresql://${DB_HOST:postgres}:${DB_PORT:5432}/${DB_NAME:skillhub}
+    username: ${DB_USER:skillhub}
+    password: ${DB_PASS:skillhub_dev}
+  data:
+    redis:
+      host: ${REDIS_HOST:redis}
+      port: ${REDIS_PORT:6379}

web/.dockerignore

@@ -0,0 +1,4 @@
+node_modules/
+dist/
+.git/
+*.md