fix: split commit from release

[Ruddickmg]

No description provided.

[Copilot]

Pull request overview

This PR refactors the release pipeline so hash generation and git commits are handled via semantic-release plugins instead of having the CircleCI hash script commit/push directly, aligning release artifacts and repository updates with the release process.

Changes:

• Configure semantic-release to prepare versioned files and commit release assets (without publishing to npm).
• Update CircleCI to generate hash artifacts (rather than committing them) and prepare the working tree for the release step.
• Add the @semantic-release/git dependency needed for the new release flow.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 4 comments.

File	Description
release.config.mjs	Adds @semantic-release/npm (no publish) and @semantic-release/git to commit release assets.
package.json	Adds @semantic-release/git dependency for the updated semantic-release configuration.
.circleci/generate-hashes.sh	Stops committing/pushing hashes; generates checksums.txt and sources.json into build output.
.circleci/config.yml	Renames/rewires the CircleCI job to generate hashes and prepares nix/sources.json before running semantic-release.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
see 1 file with indirect coverage changes

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.