CLAP-84 Feat: auth 관련 상수 클래스 추가

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- 관련: #43

Author: joowojr

src/main/java/clap/server/common/AuthConstants.java

@@ -0,0 +1,14 @@
+package clap.server.common;
+
+import lombok.Getter;
+
+@Getter
+public enum AuthConstants {
+    AUTHORIZATION("Authorization"), TOKEN_PREFIX("Bearer ");
+
+    private final String value;
+
+    AuthConstants(String value) {
+        this.value = value;
+    }
+}