resolve memory overflow by lazy-loading FF14 prompt

Author: YukiRinLL

src/main/java/com/phantoms/phantomsbackend/common/LLM/FF14Prompt.java

@@ -14,22 +14,26 @@
 @Slf4j
 @Component
 public class FF14Prompt {
-    private static String SYSTEM_PROMPT;
-
-    @PostConstruct
-    public void init() {
-        try {
-            ClassPathResource resource = new ClassPathResource("prompts/ff14-translator-prompt.md");
-            Path path = Paths.get(resource.getURI());
-            SYSTEM_PROMPT = Files.readString(path, StandardCharsets.UTF_8);
-            log.info("FF14翻译提示词加载成功，长度: {} 字符", SYSTEM_PROMPT.length());
-        } catch (IOException e) {
-            log.error("加载FF14翻译提示词失败", e);
-            SYSTEM_PROMPT = "你是最终幻想14专用翻译器。";
-        }
-    }
+    private static volatile String SYSTEM_PROMPT;
+    private static final Object LOCK = new Object();
 
     public static String getSystemPrompt() {
+        // 懒加载：首次调用时才加载
+        if (SYSTEM_PROMPT == null) {
+            synchronized (LOCK) {
+                if (SYSTEM_PROMPT == null) {
+                    try {
+                        ClassPathResource resource = new ClassPathResource("prompts/ff14-translator-prompt.md");
+                        Path path = Paths.get(resource.getURI());
+                        SYSTEM_PROMPT = Files.readString(path, StandardCharsets.UTF_8);
+                        log.info("FF14翻译提示词加载成功，长度: {} 字符", SYSTEM_PROMPT.length());
+                    } catch (IOException e) {
+                        log.error("加载FF14翻译提示词失败", e);
+                        SYSTEM_PROMPT = "你是最终幻想14专用翻译器。";
+                    }
+                }
+            }
+        }
         return SYSTEM_PROMPT;
     }
 }