[gabrielbmoro]

Summary

Adds support for analyzing only specific Dart files via positional CLI paths. When no paths are provided, EagleEye keeps scanning every Dart file under lib/.

Changes

• Parse positional arguments into CliOptions.files and document them in --help.
• Select requested files in the data layer, validating that each path exists, ends with .dart, and lives under lib/.
• Add InvalidFileSelectionException to report all invalid paths at once.
• Run config conflict validation and analysis only against the selected files.
• Deduplicate paths while preserving request order; relative and absolute paths are normalized.
• Update README, getting-started docs, and CHANGELOG.

Testing

• dart analyze passes.
• dart test passes (73 tests, including new CLI and file-selection coverage).
• Manual CLI checks for valid relative paths, absolute paths, missing files, and non-Dart files.

Related

• c82357e feat(cli): support checking specific files