fix: 修复静态文件分发时，ContentType类型未设置的bug

MINWebServer/server/FileCache.cpp

@@ -66,7 +66,7 @@ namespace MIN {
                     read(fd, fc->buf.base, fc->buf.len);
                     const char *suffix = strrchr(filepath, '.');
                     if (suffix) {
-                        fc->contentType = getContentTypeStrBySuffix(suffix);
+                        fc->contentType = getContentTypeStrBySuffix(suffix + 1);
                     }
                 } else if (S_ISDIR(fc->st.st_mode)) {
                     // DIR

MINWebServer/server/Server.cpp

@@ -111,6 +111,7 @@ namespace MIN {
                 response->content = (unsigned char *) fc->buf.base;
                 response->contentLength = fc->buf.len;
                 if (!fc->contentType.empty()) {
+                    response->contentType = getMINHttpContentTypeEnumFromStr(fc->contentType);
                     response->headers["Content-Type"] = fc->contentType;
                 }
                 response->headers["Content-Length"] = std::to_string(response->contentLength);