Refactor the whole structure, no more separation for C++ and Slint files

src/windows/AppWindow/Models.slint

@@ -0,0 +1,50 @@
+import { Date, Time } from "std-widgets.slint";
+import { CalendarDay } from "../../components/Calendar.slint";
+
+export struct Source {
+	id: int,
+	name: string,
+	selected: bool,
+	path: string
+}
+
+export struct TaskData {
+	sourceId: int,
+	eventId: int,
+	id: int,
+    title: string,
+	date: Date,
+    checked: bool,
+}
+
+export struct Event {
+	sourceId: int,
+	id: int,
+	title: string,
+	startsAt: Time,
+	endsAt: Time,
+	tasks: [TaskData],
+}
+
+export struct Day {
+	sourceId: int,
+	id: int,
+	date: Date,
+	events: [Event],
+	tasks: [TaskData],
+	isLate: bool,
+	isToday: bool,
+	relativeDaysDiff: int
+}
+
+export global AppWindowModels  {
+    in-out property<[Source]> sources-selected; 
+    in-out property<int> default-source-index;
+    in-out property<[string]> sources;
+	in-out property<bool> no-source-selected;
+	in-out property<[Day]> days;
+	in-out property<[CalendarDay]> calendar;
+	in-out property<[TaskData]> unscheduled-tasks;
+
+	callback get-source-id-from-name(string) -> int;
+}