refactor: zigify imports and correct minor mistakes

src/root.zig

@@ -0,0 +1,41 @@
+// private imports
+const container = @import("container.zig");
+const color = @import("color.zig");
+const size = @import("point.zig");
+
+// public exports
+pub const input = @import("input.zig");
+pub const testing = @import("testing.zig");
+
+pub const App = @import("app.zig").App;
+pub const Error = @import("error.zig").Error;
+// App also exports further types once initialized with the user events at compile time:
+// `App.Container`
+// `App.Element`
+pub const Renderer = @import("render.zig");
+
+// Container Configurations
+pub const Border = container.Border;
+pub const Rectangle = container.Rectangle;
+pub const Layout = container.Layout;
+
+pub const Cell = @import("cell.zig");
+pub const Color = color.Color;
+pub const Key = input.Key;
+pub const Mouse = input.Mouse;
+pub const Point = @import("point.zig").Point;
+pub const Style = @import("style.zig");
+
+test {
+    _ = @import("terminal.zig");
+    _ = @import("container.zig");
+    _ = @import("queue.zig");
+    _ = @import("error.zig");
+    _ = @import("point.zig");
+
+    _ = color;
+
+    _ = Cell;
+    _ = Key;
+    _ = Style;
+}