feat: initialize core, gui-eframe, and tui-ratatui crates and use them in the multibinary

gui-eframe/src/lib.rs

@@ -0,0 +1,4 @@
+pub fn main() {
+    #[cfg(feature = "tracing")]
+    tracing::info!("Hello from the eframe-based GUI!");
+}

gui-eframe/src/main.rs

@@ -0,0 +1 @@
+use ac_qu_ai_nt_gui_eframe::main;