Implement posix app loading (#643)

- Added POSIX desktop support for SDK builds, application packaging, and integration testing.
- Added POSIX filesystem partitions and improved application path handling.
- Added simulator support for loading and running applications dynamically.
- Improved simulator task stack handling and display startup reliability.
- Improved simulator display scaling, resizing, high-DPI support, and pointer accuracy.
- Fixed LVGL timers and input polling on POSIX. (fixes simulator with Linux on some Intel graphics platforms)
- Standardized data paths across platforms.
- Logging now works via separate task: this allows apps to write to log without it affecting their stdout (for apps that output text as relevant date for other apps, like the File Selection app)
- Fixes for app stdio

Modules/app-posix-module/tests/source/main.cpp

@@ -0,0 +1,54 @@
+#define DOCTEST_CONFIG_IMPLEMENT
+#include "doctest.h"
+#include <cassert>
+
+#include "FreeRTOS.h"
+#include "task.h"
+
+typedef struct {
+    int argc;
+    char** argv;
+    int result;
+} TestTaskData;
+
+void test_task(void* parameter) {
+    auto* data = (TestTaskData*)parameter;
+
+    doctest::Context context;
+
+    context.applyCommandLine(data->argc, data->argv);
+
+    // overrides
+    context.setOption("no-breaks", true); // don't break in the debugger when assertions fail
+
+    data->result = context.run();
+
+    vTaskEndScheduler();
+
+    vTaskDelete(nullptr);
+}
+
+int main(int argc, char** argv) {
+    TestTaskData data = {
+        .argc = argc,
+        .argv = argv,
+        .result = 0
+    };
+
+    BaseType_t task_result = xTaskCreate(
+        test_task,
+        "test_task",
+        8192,
+        &data,
+        1,
+        nullptr
+    );
+
+    if (task_result != pdPASS) {
+        return 1;
+    }
+
+    vTaskStartScheduler();
+
+    return data.result;
+}