feat: graphing in MTK toolkit, kernel exposes CPU time, Processes app Performance tab

kernel/src/Api/Syscall.hpp

@@ -407,6 +407,7 @@ namespace Montauk {
         uint8_t  _pad[3];
         char     name[64];
         uint64_t heapUsed;     // heapNext - UserHeapBase (bytes)
+        uint64_t cpuTimeMs;    // accumulated scheduler runtime
     };
 
     // Bluetooth scan result (returned by SYS_BTSCAN)