[Keyboard] Add the Osprette

[smores56]

Description

This PR adds firmware for the Osprette keyboard (with default layout) to QMK master. The following 4 boards of mine all use the same firmware, meaning this change should continue to be forward-compatible with future boards I design:

• The Osprette
• The Osprette V2
• The Osprette V3
• The Osprette MX

Types of Changes

• Core
• Bugfix
• New feature
• Enhancement/optimization
• Keyboard (addition or update)
• Keymap/layout/userspace (addition or update)
• Documentation

Issues Fixed or Closed by This PR

• N/A

Checklist

• My code follows the code style of this project: C, Python
• I have read the PR Checklist document and have made the appropriate changes.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• I have tested the changes and verified that they work and don't break anything (as well as I can manage).