[FL-3925, FL-3942, FL-3944] JS features & bugfixes (SDK 0.2) (#4075)

* feat: JS GPIO PWM, JS GUI Widget view; fix: JS EvtLoop stop on request, JS EvtLoop stop on error
* fix: f18 build
* docs: widget
* fix: js unit test
* change feature naming

Co-authored-by: あく <alleteam@gmail.com>

applications/system/js_app/modules/js_gui/icon.c

@@ -0,0 +1,61 @@
+#include "../../js_modules.h"
+#include <assets_icons.h>
+
+typedef struct {
+    const char* name;
+    const Icon* data;
+} IconDefinition;
+
+#define ICON_DEF(icon)                   \
+    (IconDefinition) {                   \
+        .name = #icon, .data = &I_##icon \
+    }
+
+static const IconDefinition builtin_icons[] = {
+    ICON_DEF(DolphinWait_59x54),
+    ICON_DEF(js_script_10px),
+};
+
+static void js_gui_icon_get_builtin(struct mjs* mjs) {
+    const char* icon_name;
+    JS_FETCH_ARGS_OR_RETURN(mjs, JS_EXACTLY, JS_ARG_STR(&icon_name));
+
+    for(size_t i = 0; i < COUNT_OF(builtin_icons); i++) {
+        if(strcmp(icon_name, builtin_icons[i].name) == 0) {
+            mjs_return(mjs, mjs_mk_foreign(mjs, (void*)builtin_icons[i].data));
+            return;
+        }
+    }
+
+    JS_ERROR_AND_RETURN(mjs, MJS_BAD_ARGS_ERROR, "no such built-in icon");
+}
+
+static void* js_gui_icon_create(struct mjs* mjs, mjs_val_t* object, JsModules* modules) {
+    UNUSED(modules);
+    *object = mjs_mk_object(mjs);
+    JS_ASSIGN_MULTI(mjs, *object) {
+        JS_FIELD("getBuiltin", MJS_MK_FN(js_gui_icon_get_builtin));
+    }
+    return NULL;
+}
+
+static void js_gui_icon_destroy(void* inst) {
+    UNUSED(inst);
+}
+
+static const JsModuleDescriptor js_gui_icon_desc = {
+    "gui__icon",
+    js_gui_icon_create,
+    js_gui_icon_destroy,
+    NULL,
+};
+
+static const FlipperAppPluginDescriptor plugin_descriptor = {
+    .appid = PLUGIN_APP_ID,
+    .ep_api_version = PLUGIN_API_VERSION,
+    .entry_point = &js_gui_icon_desc,
+};
+
+const FlipperAppPluginDescriptor* js_gui_icon_ep(void) {
+    return &plugin_descriptor;
+}