feat: 增加RAG知识库与文档基础骨架

src/main/java/com/bruce/rag/constant/RagSystemConstants.java

@@ -0,0 +1,11 @@
+package com.bruce.rag.constant;
+
+public final class RagSystemConstants {
+
+    public static final String RAG_STORE = "RAG_STORE";
+
+    public static final String RAG_DOCUMENT = "RAG_DOCUMENT";
+
+    private RagSystemConstants() {
+    }
+}