…t fields

- Increased MAC address input field width from 14 to 20 characters
- Added support for colon-separated format (e.g., 3c:58:5d:55:77:0e)
- Maintains support for hex format (e.g., 0x3c585d55770e)
- Updated parsing logic to handle both formats correctly

Fixes #96

- Remove unnecessary comments that duplicate code logic
- Fix issue where alphabetic characters couldn't be entered when field is empty
- Now only attempts parsing when input length suggests a complete MAC address
- Maintains support for both hex (0x prefix) and colon-separated formats

Addresses feedback on PR #147

- Removed unnecessary empty check condition from both MAC address fields
- The empty input is already handled by the parsing logic
- Makes the code cleaner and more concise

- Created validateAndParseMACAddress() helper function to eliminate code duplication
- Added comprehensive unit tests covering valid/invalid formats and edge cases
- Tests include hex format, colon-separated format, partial inputs, and error cases
- Improves code maintainability and makes validation logic reusable

Addresses code review suggestions for better code organization

- Added visual feedback for MAC address validation errors
- Error messages appear below input fields in red
- Success messages appear in green for valid addresses
- Added support for dash-separated format (e.g., 3c-58-5d-55-77-0e)
- Enhanced validation to show specific error reasons
- Updated tests to cover new dash format and error messages
- Improved character validation with specific invalid character feedback

Now supports three MAC address formats:
- Hex with 0x prefix: 0x3c585d55770e
- Colon-separated: 3c:58:5d:55:77:0e
- Dash-separated: 3c-58-5d-55-77-0e

- Changed validation result to use HasAddress boolean field
- Since HardwareAddr is an array type [6]uint8, it cannot be compared to nil
- Updated tests to use HasAddress instead of checking for nil
- Fixed proper copying of bytes to HardwareAddr array

This addresses the build error reported in PR #147 review

Co-authored-by: Ochi Daiki <lbfdeatq@gmail.com>

Co-authored-by: Ochi Daiki <lbfdeatq@gmail.com>

- Removed black background and white text color settings
- Form now uses default blue background like other forms
- Removed unused tcell import after color settings removal

CHANGELOG.md is now in .gitignore and should not be tracked

fix: Support both hex and colon-separated MAC address formats in inpu…