Add a CHANGELOG and a documented release/versioning process

[1nonlypiece]

📌 Description

There is a backend changelog doc but no top-level CHANGELOG or documented release process for the frontend, so released changes are hard to track for contributors and users.

🎯 Requirements and Context

• Add a Keep-a-Changelog style CHANGELOG with an Unreleased section.
• Document the release/versioning process and how entries are added.
• Cross-link the existing backend changelog doc.

🛠️ Suggested Execution

1. Fork the repo and create a branch

git checkout -b docs/changelog-release

2. Implement changes

• CHANGELOG.md — new changelog with Unreleased section
• docs/RELEASE_PROCESS.md — document versioning and release steps
• docs/backend-changelog.md — cross-link from the new process (extend)

3. Test and commit

• Run the suite: pnpm test (or npm test) and pnpm lint.
• Cover edge cases: unreleased section maintained; semver guidance; entry categories; links to backend changelog.
• Include test output (and a short note of any behavioural findings) in the PR.

Example commit message

docs: add changelog and release process

✅ Guidelines

• Minimum 95% test coverage on the new/changed lines.
• Clear, reviewer-friendly documentation and a small, focused diff.
• No regressions against existing suites.
• Timeframe: 96 hours.

🏷️ Labels

type-documentation · area-frontend · MAYBE REWARDED · GRANTFOX OSS · OFFICIAL CAMPAIGN

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