feat(ble,ui): align mesh BLE flows and extract shared two-pane UI

- improve MeshCore BLE security, pairing, MTU handling and passkey popup behavior

- align Meshtastic ack, traceroute and MQTT proxy handling with companion expectations

- extract shared two-pane nav/layout/style components and migrate chat, contacts and settings

- simplify tracker and contacts list interaction, scrolling and visual consistency

src/main.cpp

@@ -1476,13 +1476,6 @@ void setup()
 
     lv_obj_update_snap(panel, LV_ANIM_ON);
 
-#if defined(ARDUINO_M5STACK_TAB5)
-    // On Tab5 (touch-only), create a bottom virtual key bar to emulate
-    // Back/Up/Down/OK keyboard navigation.
-    extern void ui_tab5_init_virtual_keys(lv_obj_t * root);
-    ui_tab5_init_virtual_keys(menu_panel);
-#endif
-
     ::ui::status::init();
 
 #if defined(ARDUINO_T_WATCH_S3)