docs: v4 migration.

[knightedcodemonkey]

No description provided.

[Copilot]

Pull request overview

This PR finalizes the v4.0.0 release by updating the version from the release candidate (4.0.0-rc.7) to the stable version (4.0.0) and adds documentation for migrating from v3 to v4.

Key changes:

• Version bumped from 4.0.0-rc.7 to 4.0.0 in package.json and package-lock.json
• Added v4 migration documentation link to README.md

Reviewed changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated 1 comment.

File	Description
package.json	Updated version field from 4.0.0-rc.7 to 4.0.0 for stable release
package-lock.json	Updated version fields to match package.json for consistency
README.md	Added v4 migration documentation link to the documentation section

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.62%. Comparing base (ecef606) to head (170eff8).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #104   +/-   ##
=======================================
  Coverage   93.62%   93.62%           
=======================================
  Files           4        4           
  Lines        2195     2195           
=======================================
  Hits         2055     2055           
  Misses        140      140           

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