- Add flavor path configuration

### :speech_balloon: Description

**- Problem**
The getFlavors() function only searched for flavor configuration files in the current working directory, making it impossible to use flavor files stored in subdirectories like /appicons/flutter_launcher_icons-development.yaml.

**Solution**
Added --flavor-path option to specify custom search directories for flavor configuration files
Made search recursive by default to discover flavor files in subdirectories
Maintained backward compatibility - existing usage without the new flag continues to work as before

**Changes**
Enhanced getFlavors() function:
Added optional searchPath parameter (defaults to '.')
Changed from non-recursive to recursive directory search
Now finds flavor files in subdirectories

**Added command-line option:**
New --flavor-path flag to specify custom search directory
Defaults to current directory (.) for backward compatibility

# Old behavior (still works)
flutter pub run flutter_launcher_icons

# New behavior - search in custom directory
flutter pub run flutter_launcher_icons --flavor-path=appicons/brand_1

# Code change (main.dart):

```
Future> getFlavors({String searchPath = '.'}) async {
final List flavors = [];

// Recursively search through directories
await for (var item in Directory(searchPath).list(recursive: true)) {
if (item is File) {
final name = path.basename(item.path);
final match = RegExp(flavorConfigFilePattern).firstMatch(name);
if (match != null) {
flavors.add(match.group(1)!);
}
}
}
return flavors;
}

Future createIconsFromArguments(List arguments) async {
final ArgParser parser = ArgParser(allowTrailingOptions: true);
parser
..addFlag(helpFlag, abbr: 'h', help: 'Usage help', negatable: false)
// Make default null to differentiate when it is explicitly set
..addOption(
fileOption,
abbr: 'f',
help: 'Path to config file',
defaultsTo: defaultConfigFile,
)
..addFlag(verboseFlag, abbr: 'v', help: 'Verbose output', defaultsTo: false)
..addOption(
prefixOption,
abbr: 'p',
help: 'Generates config in the given path. Only Supports web platform',
defaultsTo: '.',
)
..addOption(
'flavor-path',
help: 'Path to search for flavor configuration files',
defaultsTo: '.',
);

final ArgResults argResults = parser.parse(arguments);
// creating logger based on -v flag
final logger = FLILogger(argResults[verboseFlag]);

logger.verbose('Received args ${argResults.arguments}');

if (argResults[helpFlag]) {
stdout.writeln('Generates icons for iOS and Android');
stdout.writeln(parser.usage);
exit(0);
}

// Flavors management
final flavors = await getFlavors(searchPath: argResults['flavor-path']);
final hasFlavors = flavors.isNotEmpty;

final String prefixPath = argResults[prefixOption];

// Create icons
if (!hasFlavors) {
// Load configs from given file(defaults to ./flutter_launcher_icons.yaml) or from ./pubspec.yaml

final flutterLauncherIconsConfigs =
loadConfigFileFromArgResults(argResults);
if (flutterLauncherIconsConfigs == null) {
throw NoConfigFoundException(
'No configuration found in $defaultConfigFile or in ${constants.pubspecFilePath}. '
'In case file exists in different directory use --file option',
);
}
try {
await createIconsFromConfig(
flutterLauncherIconsConfigs,
logger,
prefixPath,
);
print('\n✓ Successfully generated launcher icons');
} catch (e) {
stderr.writeln('\n✕ Could not generate launcher icons');
stderr.writeln(e);
exit(2);
}
} else {
try {
for (String flavor in flavors) {
print('\nFlavor: $flavor');
final flutterLauncherIconsConfigs =
Config.loadConfigFromFlavor(flavor, prefixPath);
if (flutterLauncherIconsConfigs == null) {
throw NoConfigFoundException(
'No configuration found for $flavor flavor.',
);
}
await createIconsFromConfig(
flutterLauncherIconsConfigs,
logger,
prefixPath,
flavor,
);
}
print('\n✓ Successfully generated launcher icons for flavors');
} catch (e) {
stderr.writeln('\n✕ Could not generate launcher icons for flavors');
stderr.writeln(e);
exit(2);
}
}
}
```