fix: macOS installer shows visible Terminal progress during setup

[ApiliumDevTeam]

Summary

First launch of Mayros.app on macOS now opens Terminal.app with a visible step-by-step setup:

  =====================================
     Mayros — First Launch Setup
  =====================================

  [1/6] Installing Mayros CLI...
         This may take 1-2 minutes.
  ✓ Mayros CLI installed

  [2/6] Configuring terminal PATH...
  ✓ PATH configured

  [3/6] Setting up AIngle Cortex...
  ✓ Cortex ready

  [4/6] Creating CLI wrapper...
  ✓ CLI wrapper created

  [5/6] Running initial configuration...
  ✓ Configuration complete

  [6/6] Starting services...
         Waiting for Cortex..... ✓
         Waiting for Gateway...... ✓

  =====================================
     Mayros is ready!
     Opening dashboard...
  =====================================

  You can now use 'mayros' from any
  terminal (open a new tab first).

  Try: mayros code

Subsequent launches skip Terminal and go directly to the portal.

What was broken

Previous approach used osascript display dialog which showed a modal with Cancelar/Aceptar buttons and a generic system icon. When user pressed a button, it broke the script flow and the installation never completed.

Test plan

• Fresh macOS install: Terminal opens, 6 steps complete, portal opens
• Second launch: Terminal doesn't open, portal opens directly
• mayros works from terminal after setup
• mayros code works from terminal after setup