编译器警告

```
/root/http_util/third_party/drogon/lib/src/SlidingWindowRateLimiter.cc: In member function ‘virtual bool drogon::SlidingWindowRateLimiter::isAllowed()’:
/root/http_util/third_party/drogon/lib/src/SlidingWindowRateLimiter.cc:37:14: warning: variable ‘startTime’ set but not used [-Wunused-but-set-variable]
37 | auto startTime = lastTime_;
| ^~~~~~~~~
/root/http_util/third_party/drogon/lib/src/HttpUtils.cc:62:10: warning: ‘drogon::CT_APPLICATION_X_JAVASCRIPT’ is deprecated: use CT_TEXT_JAVASCRIPT [-Wdeprecated-declarations]
62 | {CT_APPLICATION_X_JAVASCRIPT,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /root/http_util/third_party/drogon/lib/src/HttpUtils.h:18,
from /root/http_util/third_party/drogon/lib/src/HttpUtils.cc:15:
/root/http_util/third_party/drogon/lib/inc/drogon/HttpTypes.h:106:5: note: declared here
106 | CT_APPLICATION_X_JAVASCRIPT [[deprecated("use CT_TEXT_JAVASCRIPT")]],
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~
/root/http_util/third_party/drogon/lib/src/HttpUtils.cc: In lambda function:
/root/http_util/third_party/drogon/lib/src/HttpUtils.cc:733:23: warning: ‘drogon::CT_APPLICATION_X_JAVASCRIPT’ is deprecated: use CT_TEXT_JAVASCRIPT [-Wdeprecated-declarations]
733 | extensionMap_[CT_APPLICATION_X_JAVASCRIPT] =
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~
/root/http_util/third_party/drogon/lib/inc/drogon/HttpTypes.h:106:5: note: declared here
106 | CT_APPLICATION_X_JAVASCRIPT [[deprecated("use CT_TEXT_JAVASCRIPT")]],
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~
/root/http_util/third_party/drogon/lib/src/Utilities.cc: In function ‘void drogon::utils::dateToCustomFormattedString(const std::string&, std::string&, const trantor::Date&)’:
/root/http_util/third_party/drogon/lib/src/Utilities.cc:1042:12: warning: unused variable ‘seconds’ [-Wunused-variable]
1042 | time_t seconds = static_cast(nowSecond);
| ^~~~~~~
/root/http_util/third_party/drogon/lib/src/HttpClientImpl.cc: In member function ‘void drogon::HttpClientImpl::handleResponse(const drogon::HttpResponseImplPtr&, std::pair, std::function&)> >&&, const trantor::TcpConnectionPtr&)’:
/root/http_util/third_party/drogon/lib/src/HttpClientImpl.cc:552:11: warning: unused variable ‘type’ [-Wunused-variable]
552 | auto &type = resp->getHeaderBy("content-type");
| ^~~~
/root/http_util/third_party/drogon/lib/src/AccessLogger.cc: In member function ‘virtual void drogon::plugin::AccessLogger::initAndStart(const Json::Value&)’:
/root/http_util/third_party/drogon/lib/src/AccessLogger.cc:263:22: warning: comparison of unsigned expression in ‘>= 0’ is always true [-Wtype-limits]
263 | if (maxFiles >= 0)
| ~~~~~~~~~^~~~
/root/http_util/third_party/drogon/lib/src/HttpResponseImpl.cc: In static member function ‘static drogon::HttpResponsePtr drogon::HttpResponse::newStreamResponse(const std::function&, const std::string&, drogon::ContentType, const std::string&, const drogon::HttpRequestPtr&)’:
/root/http_util/third_party/drogon/lib/src/HttpResponseImpl.cc:426:18: warning: unused variable ‘contentType’ [-Wunused-variable]
426 | auto contentType = type;
| ^~~~~~~~~~~
/root/http_util/third_party/drogon/lib/src/HttpResponseImpl.cc:446:18: warning: unused variable ‘contentType’ [-Wunused-variable]
446 | auto contentType = type;
| ^~~~~~~~~~~
/root/http_util/third_party/drogon/lib/src/HttpServer.cc: In static member function ‘static void drogon::HttpServer::onMessage(const trantor::TcpConnectionPtr&, trantor::MsgBuffer*)’:
/root/http_util/third_party/drogon/lib/src/HttpServer.cc:222:44: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses]
222 | if (parseRes >= 2 || parseRes == 1 && !req->isStreamMode())
| ~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
/root/http_util/third_party/drogon/lib/src/HttpAppFrameworkImpl.cc: In member function ‘virtual void drogon::HttpAppFrameworkImpl::addPlugin(const std::string&, const std::vector >&, const Json::Value&)’:
/root/http_util/third_party/drogon/lib/src/HttpAppFrameworkImpl.cc:379:21: warning: loop variable ‘dep’ creates a copy from type ‘const std::__cxx11::basic_string’ [-Wrange-loop-construct]
379 | for (const auto dep : dependencies)
| ^~~
/root/http_util/third_party/drogon/lib/src/HttpAppFrameworkImpl.cc:379:21: note: use reference type to prevent copying
379 | for (const auto dep : dependencies)
| ^~~
| &
/root/http_util/third_party/drogon/lib/src/HttpAppFrameworkImpl.cc: In member function ‘virtual void drogon::HttpAppFrameworkImpl::addPlugins(const Json::Value&)’:
/root/http_util/third_party/drogon/lib/src/HttpAppFrameworkImpl.cc:394:21: warning: loop variable ‘config’ creates a copy from type ‘const Json::Value’ [-Wrange-loop-construct]
394 | for (const auto config : configs)
| ^~~~~~
/root/http_util/third_party/drogon/lib/src/HttpAppFrameworkImpl.cc:394:21: note: use reference type to prevent copying
394 | for (const auto config : configs)

/root/http_util/third_party/drogon/examples/async_stream/RequestStreamExampleCtrl.cc: In lambda function:
/root/http_util/third_party/drogon/examples/async_stream/RequestStreamExampleCtrl.cc:89:33: warning: missing initializer for member ‘RequestStreamExampleCtrl::stream_upload(const drogon::HttpRequestPtr&, drogon::RequestStreamPtr&&, std::function&)>&&) const::Entry::tmpName’ [-Wmissing-field-initializers]
89 | files->push_back({std::move(header)});
| ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~
/root/http_util/third_party/drogon/examples/async_stream/RequestStreamExampleCtrl.cc:89:33: warning: missing initializer for member ‘RequestStreamExampleCtrl::stream_upload(const drogon::HttpRequestPtr&, drogon::RequestStreamPtr&&, std::function&)>&&) const::Entry::file’ [-Wmissing-field-initializers]

/root/http_util/third_party/drogon/drogon_ctl/version.cc: In member function ‘virtual void drogon_ctl::version::handleCommand(std::vector >&)’:
/root/http_util/third_party/drogon/drogon_ctl/version.cc:36:16: warning: unused variable ‘tlsSupported’ [-Wunused-variable]
36 | const bool tlsSupported = drogon::utils::supportsTls();
| ^~~~~~~~~~~~
[ 82%] Linking CXX shared library libhttp_util.so
[ 82%] Built target http_util
/root/http_util/third_party/drogon/drogon_ctl/create_model.cc:49:20: warning: ‘std::string escapeConnString(const std::string&)’ defined but not used [-Wunused-function]
49 | static std::string escapeConnString(const std::string &str)
| ^~~~~~~~~~~~~~~~
/root/http_util/third_party/drogon/drogon_ctl/create_model.cc:40:20: warning: ‘std::string toLower(const std::string&)’ defined but not used [-Wunused-function]
40 | static std::string toLower(const std::string &str)
```

有一些值得改的， 供您参考

Reproduce the compiler warnings, then inspect the listed locations in lib/src/SlidingWindowRateLimiter.cc, HttpUtils.cc, Utilities.cc, HttpClientImpl.cc, AccessLogger.cc, HttpResponseImpl.cc, HttpServer.cc, HttpAppFrameworkImpl.cc, examples/async_stream/RequestStreamExampleCtrl.cc, and drogon_ctl/*.cc. Determine which warnings are actionable and verify that the project builds without the addressed warnings.

Written by the indexing model from the issue text.