feat: bootstrap enum component

[coisa]

Summary

• bootstrap the new fast-forward/enum component repository
• add enum helpers, traits, common enums, and state machine support
• wire the package into the fast-forward/dev-tools consumer flow

Included in this PR

• Helper\\EnumHelper with names, values, maps, lookups, labels, and descriptions
• traits for names, values, options, comparisons, labels, and descriptions
• state machine helpers with transition validation
• reusable common enums: Environment, Priority, Severity, Weekday, and Month
• package tests, README, Composer setup, and synchronized repo assets

Follow-up

• dev-tools generated LICENSE HTML escaping bug tracked in LICENSE generator HTML-escapes maintainer email dev-tools#179
• local dev-tools standards flow still wants follow-up work around docs/reporting and coverage metadata polish

Closes #1

[github-actions]

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