[FL-872] Furi, API-HAL, App-Loader cleanup and improvements (#334)

* Furi: replace obsolete furiac_exit with osThreadExit, drop obsolete apis and test. Rename systemd to flipper and move to separate file, cleanup. ApiHal: Rename timebase to os and move freertos hooks there, move insomnia api to power module.
* Furi: new thread helper
* Furi: cleanup thread documentation
* Flipper, AppLoader: update to use FuriThread. Update tasks signatures to match FuriThreadCallback signature.
* F4: rename API_HAL_TIMEBASE_DEBUG to API_HAL_OS_DEBUG
* Applications: rename FuriApplication to FlipperApplication, use FuriThreadCallback signature for apps.
* C++ app template sample, new exit method

core/furi/thread.c

@@ -0,0 +1,122 @@
+#include "thread.h"
+#include "memmgr.h"
+#include "check.h"
+
+#include <m-string.h>
+
+struct FuriThread {
+    FuriThreadState state;
+    int32_t ret;
+
+    FuriThreadCallback callback;
+    void* context;
+
+    FuriThreadStateCallback state_callback;
+    void* state_context;
+
+    osThreadAttr_t attr;
+    osThreadId_t id;
+};
+
+void furi_thread_set_state(FuriThread* thread, FuriThreadState state) {
+    furi_assert(thread);
+    thread->state = state;
+    if(thread->state_callback) {
+        thread->state_callback(state, thread->state_context);
+    }
+}
+
+void furi_thread_body(void* context) {
+    furi_assert(context);
+    FuriThread* thread = context;
+
+    furi_assert(thread->state == FuriThreadStateStarting);
+    furi_thread_set_state(thread, FuriThreadStateRunning);
+
+    thread->ret = thread->callback(thread->context);
+
+    furi_assert(thread->state == FuriThreadStateRunning);
+    furi_thread_set_state(thread, FuriThreadStateStopped);
+
+    osThreadExit();
+}
+
+FuriThread* furi_thread_alloc() {
+    FuriThread* thread = furi_alloc(sizeof(FuriThread));
+
+    return thread;
+}
+
+void furi_thread_free(FuriThread* thread) {
+    furi_assert(thread);
+    furi_assert(thread->state == FuriThreadStateStopped);
+
+    if(thread->attr.name) free((void*)thread->attr.name);
+    free(thread);
+}
+
+void furi_thread_set_name(FuriThread* thread, const char* name) {
+    furi_assert(thread);
+    furi_assert(thread->state == FuriThreadStateStopped);
+    if(thread->attr.name) free((void*)thread->attr.name);
+    thread->attr.name = strdup(name);
+}
+
+void furi_thread_set_stack_size(FuriThread* thread, size_t stack_size) {
+    furi_assert(thread);
+    furi_assert(thread->state == FuriThreadStateStopped);
+    thread->attr.stack_size = stack_size;
+}
+
+void furi_thread_set_callback(FuriThread* thread, FuriThreadCallback callback) {
+    furi_assert(thread);
+    furi_assert(thread->state == FuriThreadStateStopped);
+    thread->callback = callback;
+}
+
+void furi_thread_set_context(FuriThread* thread, void* context) {
+    furi_assert(thread);
+    furi_assert(thread->state == FuriThreadStateStopped);
+    thread->context = context;
+}
+
+void furi_thread_set_state_callback(FuriThread* thread, FuriThreadStateCallback callback) {
+    furi_assert(thread);
+    furi_assert(thread->state == FuriThreadStateStopped);
+    thread->state_callback = callback;
+}
+
+void furi_thread_set_state_context(FuriThread* thread, void* context) {
+    furi_assert(thread);
+    furi_assert(thread->state == FuriThreadStateStopped);
+    thread->state_context = context;
+}
+
+bool furi_thread_start(FuriThread* thread) {
+    furi_assert(thread);
+    furi_assert(thread->callback);
+    furi_assert(thread->state == FuriThreadStateStopped);
+    furi_thread_set_state(thread, FuriThreadStateStarting);
+    thread->id = osThreadNew(furi_thread_body, thread, &thread->attr);
+    if(thread->id) {
+        return true;
+    } else {
+        furi_assert(thread->state == FuriThreadStateStarting);
+        furi_thread_set_state(thread, FuriThreadStateStopped);
+        return false;
+    }
+}
+
+osStatus_t furi_thread_terminate(FuriThread* thread) {
+    furi_assert(thread);
+    osStatus_t ret = osThreadTerminate(thread->id);
+    if(ret == osOK) {
+        furi_thread_set_state(thread, FuriThreadStateStopped);
+    }
+    return ret;
+}
+
+osStatus_t furi_thread_join(FuriThread* thread) {
+    furi_assert(thread);
+    return osThreadJoin(thread->id);
+}