Stable CRAN restoration

FinancialInstrument 1.4.1

This release marks the return of FinancialInstrument to CRAN and the transition of package maintenance to Justin M. Shea, succeeding Ross Bennett. Many thanks to @rossb34 and the original contributors for their years of development and stewardship.

Highlights

• Restored CRAN compliance across documentation, examples, namespace declarations, and package metadata.
• Improved compatibility and robustness of instrument persistence, including saveInstruments() and loadInstruments().
• Made alltick2sec() progress reporting optional and non-intrusive with a new verbose = FALSE argument.
• Modernized examples to use temporary directories and exported package interfaces rather than internal objects.
• Added complete return-value documentation across the exported API.
• Fixed S3 registration for expires.spread and confirmed expires() as part of the exported API.
• Migrated the test suite from testthat to tinytest, reducing dependencies and improving test execution.
• Improved cross-platform tests, including timezone, frequency-alignment, and intraday cases.
• Refactored internal quantmod-related helpers and improved package documentation.
• Added GitHub Actions CI and a new README covering installation and basic usage.

This release is primarily focused on restoring, stabilizing, and modernizing the existing package while maintaining compatibility with the broader FinancialInstrument/blotter/quantstrat ecosystem.