refactor: migrate MICRO_PIP to fine-grained feature flags

Replace monolithic MICRO_PIP/PIP_MICRO with granular flags:

Feature flags (CMake options + platform auto-detection):
- PIP_NO_FILESYSTEM, PIP_NO_THREADS, PIP_NO_SOCKET
- PIP_NO_PROCESS, PIP_NO_DYNLIB, PIP_NO_FFT, PIP_NO_SERIAL

Embedded optimization flag:
- PIP_EMBEDDED (auto-set for Pico SDK and FreeRTOS)
  Controls buffer sizes, time stubs, terminal fallback, init stubs

Platform blocks in CMakeLists.txt:
- Pico SDK: auto-disables FS, PROCESS, DYNLIB, FFT, SERIAL;
  conditionally disables THREADS (no FreeRTOS) and SOCKET (no LWIP)
- FreeRTOS: auto-disables FS, PROCESS, DYNLIB, FFT, SERIAL;
  conditionally disables SOCKET (no LWIP)
- Android: auto-disables PROCESS, DYNLIB, FFT

Updated 96 files across libs/, utils/, tests/, and CMakeLists.txt.
Builds verified for Linux (547 tests pass) and Pico SDK (100%).
Removed all MICRO_PIP and PIP_MICRO references (0 remaining).

libs/main/io_utils/pidiagnostics.h

@@ -29,6 +29,7 @@
 #include "pitimer.h"
 
 
+#ifndef PIP_NO_THREADS
 //! \~\ingroup IO-Utils
 //! \brief
 //! \~english Connection diagnostics for packet frequency, throughput and receive quality
@@ -56,7 +57,7 @@ public:
 	enum Quality {
 		Unknown = 1 /** \~english No receive history yet \~russian История приема еще отсутствует */,
 		Failure = 2 /** \~english No correct packets in the recent window \~russian В недавнем окне нет корректных пакетов */,
-		Bad     = 3 /** \~english Correct packets are at most 20 percent \~russian Корректных пакетов не более 20 процентов */,
+		Bad = 3 /** \~english Correct packets are at most 20 percent \~russian Корректных пакетов не более 20 процентов */,
 		Average =
 			4 /** \~english Correct packets are above 20 and up to 80 percent \~russian Корректных пакетов больше 20 и до 80 процентов */
 			,
@@ -235,5 +236,6 @@ inline bool operator!=(const PIDiagnostics::Entry & f, const PIDiagnostics::Entr
 inline bool operator<(const PIDiagnostics::Entry & f, const PIDiagnostics::Entry & s) {
 	return f.bytes_ok < s.bytes_ok;
 }
+#endif // PIP_NO_THREADS
 
 #endif // PIDIAGNOSTICS_H