docs: Update GUI launch instructions in README and INSTALL.md

- Added instructions for rebuilding native modules for Electron
- Removed "not implemented yet" note from GUI command
- Added troubleshooting note for GUI issues

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: ahmadzein

INSTALL.md

@@ -62,10 +62,15 @@ portman kill 3000
 
 ### GUI
 ```bash
-# Launch the GUI (not implemented yet)
+# Launch the GUI
 portman gui
 ```
 
+If you encounter issues with the GUI, rebuild the native modules:
+```bash
+npm rebuild better-sqlite3 --runtime=electron --target=28.0.0
+```
+
 ## Troubleshooting
 
 ### Command not found

README.md

@@ -83,7 +83,11 @@ Launch the GUI application:
 portman gui
 ```
 
-Or use the desktop application directly after installation.
+**Note**: The GUI feature requires the project to be built first. If you encounter issues, run:
+```bash
+npm run build:gui
+npm rebuild better-sqlite3 --runtime=electron --target=28.0.0
+```
 
 ## Development