Code Cleanup: unused includes, useless checks, unused variables, etc... (#3696)

* Remove unnecessary checks
* Sublime: never insert missing headers
* Cleanup furi defines use
* Cleanup startup. Cleanup linker scripts. Explicitly define all interrupts hadlers, including uninmplemented one.
* Startup routine in C
* Drop assembler startup
* Move linker defines to stm32wb55_linker.h, cleanup naming, unify usage. Mpu: protect last 32b of main stack. Document various obscure things.
* Move furi_hal_switch documentation to appropriate place, use 0x0 for updater jump.
* UnitTests: move all temporary test files into tmp folder

---------

Co-authored-by: SG <who.just.the.doctor@gmail.com>

furi/core/common_defines.h

@@ -67,6 +67,14 @@ void __furi_critical_exit(__FuriCriticalInfo info);
 #define FURI_CHECK_RETURN __attribute__((__warn_unused_result__))
 #endif
 
+#ifndef FURI_NAKED
+#define FURI_NAKED __attribute__((naked))
+#endif
+
+#ifndef FURI_DEFAULT
+#define FURI_DEFAULT(x) __attribute__((weak, alias(x)))
+#endif
+
 #ifdef __cplusplus
 }
 #endif

furi/core/memmgr_heap.c

@@ -39,6 +39,7 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <stm32wbxx.h>
+#include <stm32wb55_linker.h>
 #include <core/log.h>
 #include <core/common_defines.h>
 
@@ -63,8 +64,6 @@ task.h is included from an application file. */
 #define heapBITS_PER_BYTE ((size_t)8)
 
 /* Heap start end symbols provided by linker */
-extern const void __heap_start__;
-extern const void __heap_end__;
 uint8_t* ucHeap = (uint8_t*)&__heap_start__;
 
 /* Define the linked list structure.  This is used to link free blocks in order

furi/core/message_queue.h

@@ -4,7 +4,7 @@
  */
 #pragma once
 
-#include "core/base.h"
+#include "base.h"
 
 #ifdef __cplusplus
 extern "C" {

furi/core/pubsub.c

@@ -20,7 +20,6 @@ FuriPubSub* furi_pubsub_alloc(void) {
     FuriPubSub* pubsub = malloc(sizeof(FuriPubSub));
 
     pubsub->mutex = furi_mutex_alloc(FuriMutexTypeNormal);
-    furi_assert(pubsub->mutex);
 
     FuriPubSubSubscriptionList_init(pubsub->items);
 

furi/core/record.c

@@ -39,7 +39,6 @@ static void furi_record_erase(const char* name, FuriRecordData* record_data) {
 void furi_record_init(void) {
     furi_record = malloc(sizeof(FuriRecord));
     furi_record->mutex = furi_mutex_alloc(FuriMutexTypeNormal);
-    furi_check(furi_record->mutex);
     FuriRecordDataDict_init(furi_record->records);
 }
 

furi/core/timer.h

@@ -4,7 +4,7 @@
  */
 #pragma once
 
-#include "core/base.h"
+#include "base.h"
 
 #ifdef __cplusplus
 extern "C" {