Migrate CHANGELOG.md to GitHub Releases redirect

[schmidtw]

Ideal State Gap

The CHANGELOG.md file contains a maintained changelog with version entries. The ideal state requires it to either be absent or contain only a note directing readers to GitHub Releases.

Current State

CHANGELOG.md contains detailed version history with entries for v0.1.0 through v0.11.4.

Expected State

CHANGELOG.md should either:

1. Be removed entirely, OR
2. Contain only a brief note like: "See GitHub Releases for the changelog."

Checklist

• Decide whether to remove or replace CHANGELOG.md
• If replacing, create a simple redirect to GitHub Releases
• If removing, delete the file
• Ensure existing release notes are captured in GitHub Releases