refactor: rename PIP_NO_\* to PIP_HAS_\* with inverted logic

All feature flags now use positive naming (enabled by default):
- PIP_HAS_FILESYSTEM, PIP_HAS_THREADS, PIP_HAS_SOCKET
- PIP_HAS_PROCESS, PIP_HAS_DYNLIB, PIP_HAS_FFT, PIP_HAS_SERIAL

Preprocessor guards inverted:
- #ifndef PIP_NO_X → #ifdef PIP_HAS_X
- #ifdef PIP_NO_X → #ifndef PIP_HAS_X

CMake options default ON instead of OFF.
Platform blocks set flags OFF to disable features.

85 files transformed via Python script + 2 manual fixes.

libs/main/io_utils/pibroadcast.h

@@ -34,7 +34,7 @@
 //! \~\brief
 //! \~english Multi-channel sender and receiver over multicast, broadcast and loopback endpoints.
 //! \~russian Многоканальный отправитель и приемник через multicast-, broadcast- и loopback-конечные точки.
-#ifndef PIP_NO_SOCKET
+#ifdef PIP_HAS_SOCKET
 class PIP_IO_UTILS_EXPORT PIBroadcast
 	: public PIThread
 	, public PIEthUtilBase {
@@ -183,6 +183,6 @@ private:
 	int lo_pcnt;
 	bool _started, _send_only, _reinit;
 };
-#endif // PIP_NO_SOCKET
+#endif // PIP_HAS_SOCKET
 
 #endif // PIBROADCAST_H