fix: add exit 0 after main to prevent bash hanging on curl pipe

exec < /dev/tty redirects stdin to terminal for interactive prompts,
but after main() finishes bash keeps reading from tty instead of exiting.

Author: fullstackjam

src/lib/server/install-script.test.ts

@@ -116,7 +116,7 @@ describe('generateInstallScript', () => {
 		const script = generateInstallScript('testuser', 'my-config', '', '');
 
 		expect(script).toContain('main()');
-		expect(script).toMatch(/main "\$@"\s*$/);
+		expect(script).toMatch(/main "\$@"\s*\nexit 0\s*$/);
 		expect(script).toContain('exec < /dev/tty');
 	});
 

src/lib/server/install-script.ts

@@ -293,5 +293,6 @@ echo "Installation complete!"
 }
 
 main "\$@"
+exit 0
 `;
 }