feat(cli): add beautiful colored output and fix daemon exit bug

Major improvements:
- Created color theme system (ts/colors.ts) with ANSI colors
- Enhanced logger with colors, table formatting, and styled boxes
- Fixed daemon exit bug - now stays running when no UPS configured
- Added config hot-reload with file watcher for live updates
- Beautified CLI help output with color-coded commands
- Added showcase test demonstrating all output features
- Fixed ANSI code handling for perfect table/box alignment

Features:
- Color-coded messages (success=green, error=red, warning=yellow, info=cyan)
- Status symbols (●○◐◯ for running/stopped/starting/unknown)
- Battery level colors (green>60%, yellow 30-60%, red<30%)
- Table formatting with auto-sizing and column alignment
- Styled boxes (success, error, warning, info styles)
- Hot-reload: daemon watches config file and reloads automatically
- Idle mode: daemon stays alive when no devices, checks periodically

Daemon improvements:
- No longer exits when no UPS devices configured
- Enters idle monitoring loop waiting for config
- File watcher detects config changes in real-time
- Auto-reloads and starts monitoring when devices added
- Logs warnings instead of errors for missing devices

Technical fixes:
- Strip ANSI codes when calculating text width for alignment
- Use visible length for padding calculations in tables and boxes
- Properly handle colored text in table cells and box lines

Breaking changes: None (backward compatible)

ts/cli.ts

@@ -1,6 +1,7 @@
 import { execSync } from 'node:child_process';
 import { Nupst } from './nupst.ts';
 import { logger } from './logger.ts';
+import { theme, symbols } from './colors.ts';
 
 /**
  * Class for handling CLI commands
@@ -475,58 +476,83 @@ export class NupstCli {
    * Display help message
    */
   private showHelp(): void {
-    logger.log(`
-NUPST - UPS Shutdown Tool
+    console.log('');
+    logger.highlight('NUPST - UPS Shutdown Tool');
+    logger.dim('Deno-powered UPS monitoring and shutdown automation');
+    console.log('');
 
-Usage:
-  nupst <command> [options]
+    // Usage section
+    logger.log(theme.info('Usage:'));
+    logger.log(`  ${theme.command('nupst')} ${theme.dim('<command> [options]')}`);
+    console.log('');
 
-Commands:
-  service <subcommand>      - Manage systemd service
-  ups <subcommand>          - Manage UPS devices
-  group <subcommand>        - Manage UPS groups
-  config [show]             - Display current configuration
-  update                    - Update NUPST from repository (requires root)
-  uninstall                 - Completely remove NUPST from system (requires root)
-  help, --help, -h          - Show this help message
-  --version, -v             - Show version information
+    // Main commands section
+    logger.log(theme.info('Commands:'));
+    this.printCommand('service <subcommand>', 'Manage systemd service');
+    this.printCommand('ups <subcommand>', 'Manage UPS devices');
+    this.printCommand('group <subcommand>', 'Manage UPS groups');
+    this.printCommand('config [show]', 'Display current configuration');
+    this.printCommand('update', 'Update NUPST from repository', theme.dim('(requires root)'));
+    this.printCommand('uninstall', 'Completely remove NUPST', theme.dim('(requires root)'));
+    this.printCommand('help, --help, -h', 'Show this help message');
+    this.printCommand('--version, -v', 'Show version information');
+    console.log('');
 
-Service Subcommands:
-  nupst service enable      - Install and enable systemd service (requires root)
-  nupst service disable     - Stop and disable systemd service (requires root)
-  nupst service start       - Start the systemd service
-  nupst service stop        - Stop the systemd service
-  nupst service restart     - Restart the systemd service
-  nupst service status      - Show service and UPS status
-  nupst service logs        - Show service logs in real-time
-  nupst service start-daemon - Start daemon process directly
+    // Service subcommands
+    logger.log(theme.info('Service Subcommands:'));
+    this.printCommand('nupst service enable', 'Install and enable systemd service', theme.dim('(requires root)'));
+    this.printCommand('nupst service disable', 'Stop and disable systemd service', theme.dim('(requires root)'));
+    this.printCommand('nupst service start', 'Start the systemd service');
+    this.printCommand('nupst service stop', 'Stop the systemd service');
+    this.printCommand('nupst service restart', 'Restart the systemd service');
+    this.printCommand('nupst service status', 'Show service and UPS status');
+    this.printCommand('nupst service logs', 'Show service logs in real-time');
+    this.printCommand('nupst service start-daemon', 'Start daemon process directly');
+    console.log('');
 
-UPS Subcommands:
-  nupst ups add             - Add a new UPS device
-  nupst ups edit [id]       - Edit a UPS device (default if no ID)
-  nupst ups remove <id>     - Remove a UPS device by ID
-  nupst ups list (or ls)    - List all configured UPS devices
-  nupst ups test            - Test UPS connections
+    // UPS subcommands
+    logger.log(theme.info('UPS Subcommands:'));
+    this.printCommand('nupst ups add', 'Add a new UPS device');
+    this.printCommand('nupst ups edit [id]', 'Edit a UPS device (default if no ID)');
+    this.printCommand('nupst ups remove <id>', 'Remove a UPS device by ID');
+    this.printCommand('nupst ups list (or ls)', 'List all configured UPS devices');
+    this.printCommand('nupst ups test', 'Test UPS connections');
+    console.log('');
 
-Group Subcommands:
-  nupst group add           - Add a new UPS group
-  nupst group edit <id>     - Edit an existing UPS group
-  nupst group remove <id>   - Remove a UPS group by ID
-  nupst group list (or ls)  - List all UPS groups
+    // Group subcommands
+    logger.log(theme.info('Group Subcommands:'));
+    this.printCommand('nupst group add', 'Add a new UPS group');
+    this.printCommand('nupst group edit <id>', 'Edit an existing UPS group');
+    this.printCommand('nupst group remove <id>', 'Remove a UPS group by ID');
+    this.printCommand('nupst group list (or ls)', 'List all UPS groups');
+    console.log('');
 
-Options:
-  --debug, -d              - Enable debug mode for detailed SNMP logging
-                             (Example: nupst ups test --debug)
+    // Options
+    logger.log(theme.info('Options:'));
+    this.printCommand('--debug, -d', 'Enable debug mode for detailed SNMP logging');
+    logger.dim('                     (Example: nupst ups test --debug)');
+    console.log('');
 
-Examples:
-  nupst service enable     - Install and start the service
-  nupst ups add            - Add a new UPS interactively
-  nupst group list         - Show all configured groups
-  nupst config             - Display current configuration
+    // Examples
+    logger.log(theme.info('Examples:'));
+    logger.dim('  nupst service enable     # Install and start the service');
+    logger.dim('  nupst ups add            # Add a new UPS interactively');
+    logger.dim('  nupst group list         # Show all configured groups');
+    logger.dim('  nupst config             # Display current configuration');
+    console.log('');
 
-Note: Old command format (e.g., 'nupst add') still works but is deprecated.
-      Use the new format (e.g., 'nupst ups add') going forward.
-`);
+    // Note about deprecated commands
+    logger.warn('Note: Old command format (e.g., \'nupst add\') still works but is deprecated.');
+    logger.dim('      Use the new format (e.g., \'nupst ups add\') going forward.');
+    console.log('');
+  }
+
+  /**
+   * Helper to print a command with description
+   */
+  private printCommand(command: string, description: string, extra?: string): void {
+    const paddedCommand = command.padEnd(30);
+    logger.log(`  ${theme.command(paddedCommand)} ${description}${extra ? ' ' + extra : ''}`);
   }
 
   /**