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/state_machine/pistatemachine_transition.h

@@ -5,8 +5,8 @@
 //! \~russian Объявляет переходы, используемые в PIStateMachine
 /*
     PIP - Platform Independent Primitives
-	State machine transition
-	Ivan Pelipenko peri4ko@yandex.ru
+    State machine transition
+    Ivan Pelipenko peri4ko@yandex.ru
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU Lesser General Public License as published by
@@ -142,7 +142,9 @@ private:
 	void enabled() override;
 	void disabled() override;
 
+#ifndef PIP_NO_THREADS
 	PITimer timer;
+#endif
 };
 
 #endif