chore: Release 2.2.8

[TheRealAgentK]

Summary

• bump raygun from 2.2.7 to 2.2.8
• document the CI, test, lint, type-definition, and development lockfile maintenance included since 2.2.7
• clarify that this maintenance release does not change the public API or runtime behavior

Release classification

Patch release. The included updates affect development tooling, CI, type definitions, and development dependency lockfiles only.

Validation

• npm test (258 passing)
• npm run test:cjs
• npm run eslint
• npm run tseslint
• Prettier check
• npm audit (0 vulnerabilities)
• npm audit --omit=dev (0 vulnerabilities)
• npm publish --dry-run (raygun@2.2.8, 28 files)

Release workflow

After approval and green CI, publish raygun@2.2.8 to npm before merging this PR, then create GitHub release v2.2.8 from the merged release commit as documented in RELEASING.md.