feat: 新增嵌入式分布式调度底座

- 提供通用调度 API、Quartz JDBC Provider 与独立 Starter

- 补充 MySQL、PostgreSQL、H2 建表脚本与接入校验

- 同步完善 Federation 与 Scheduler 模块说明

easy-agents-scheduler/pom.xml

@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <parent>
+        <groupId>com.easyagents</groupId>
+        <artifactId>easy-agents</artifactId>
+        <version>${revision}</version>
+    </parent>
+
+    <artifactId>easy-agents-scheduler</artifactId>
+    <packaging>pom</packaging>
+    <name>easy-agents-scheduler</name>
+
+    <modules>
+        <module>easy-agents-scheduler-core</module>
+        <module>easy-agents-scheduler-quartz</module>
+        <module>easy-agents-scheduler-spring-boot-starter</module>
+    </modules>
+</project>