common : separate whisper sources (#2846)

* common : separate whisper sources

* examples : add chrono

* examples : add more headers

examples/lsp/lsp.cpp

@@ -3,14 +3,15 @@
 #include "whisper.h"
 #include "json.hpp"
 
-#include <iostream>
 #include <cassert>
+#include <chrono>
 #include <cstdio>
+#include <deque>
+#include <iostream>
+#include <set>
 #include <string>
 #include <thread>
 #include <vector>
-#include <deque>
-#include <set>
 
 using json = nlohmann::json;