Add flip option support

[11bit]

Closes #66

[Copilot]

Pull request overview

This PR adds support for the flip option to imgproxy-js-core, allowing users to flip images horizontally and/or vertically. The implementation follows the established patterns used by other boolean-like options in the codebase.

Key Changes:

• Adds flip option type definitions with support for boolean-like values (true, false, 1, 0, "t", "f")
• Implements flip option builder that generates the fl:horizontal:vertical URL format
• Includes comprehensive test coverage for various value types and edge cases

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
src/types/flip.ts	Defines FlipOptions type and FlipOptionsPartial interface with horizontal/vertical properties supporting boolean-like values
src/options/flip.ts	Implements test and build functions for flip option, including shorthand fl support
tests/optionsBasic/flip.test.ts	Comprehensive test suite covering various input types, defaults, and both flip/fl shorthands
src/types/index.ts	Integrates FlipOptionsPartial into the main Options type
src/options/index.ts	Exports flip module for public API access
.changeset/brown-mangos-fetch.md	Documents the feature addition as a minor version change

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[Copilot]

@11bit I've opened a new pull request, #74, to work on those changes. Once the pull request is ready, I'll request review from you.

[Copilot]

@11bit I've opened a new pull request, #75, to work on those changes. Once the pull request is ready, I'll request review from you.