feat(01-02): implement terminal init/restore and panic hook

- init_terminal() enables raw mode and clears main screen via Viewport::Fullscreen
- No alternate screen buffer used (deliberate BBS immersive approach)
- restore_terminal() disables raw mode and shows cursor using let _ for all calls
- install_panic_hook() restores terminal, prints BBS-themed message, delegates to original hook
- Use ratatui::crossterm re-export (crossterm is transitive dep only)
- All panic hook operations use let _ or eprintln! — no unwrap() or ? inside hook

src/main.rs

@@ -0,0 +1,25 @@
+mod config;
+mod terminal;
+
+fn main() {
+    // 1. Detect login shell BEFORE stripping argv[0]
+    let is_login_shell = config::detect_login_shell();
+
+    // 2. Parse CLI (strips dash from argv[0] internally)
+    let cli = config::parse_cli();
+
+    // 3. Resolve config path and load config
+    let config_path = config::resolve_config_path(cli.config.as_deref());
+    let app_config = match config::load_config(&config_path) {
+        Ok(c) => c,
+        Err(e) => {
+            config::print_config_error(&e);
+            std::process::exit(1);
+        }
+    };
+
+    // Phase 1 placeholder: print loaded config for verification
+    // This will be replaced by terminal init + event loop in Plan 03
+    println!("Config loaded: {:?}", app_config);
+    println!("Login shell: {}", is_login_shell);
+}