fix: Update version to 0.7.1 and simplify saveTo parameter descriptio…

[freema]

This pull request introduces a patch release (v0.7.1) focused on improving documentation and updating version references throughout the project. The most significant change is the simplification of the saveTo parameter description in the screenshot tools, which removes opinionated usage instructions to prevent influencing AI assistant behavior. Additionally, all version references have been updated to reflect the new release.

Release and version updates:

• Updated package.json, src/config/constants.ts, and related tests to reference version 0.7.1. [1] [2] [3] [4]
• Added a new section for 0.7.1 in CHANGELOG.md and linked the release comparison URL. [1] [2]

Documentation improvements:

• Simplified the saveTo parameter description in src/tools/screenshot.ts to remove opinionated usage instructions and clarify its purpose.…n in screenshot tools