Career Map role pages now show what a role actually involves

Career Map role pages went beyond a short description and a skill list. Each of the 11 launch roles now shows:

- What the role actually covers, and other titles it goes by - What this role is NOT — to cut down on title confusion between similar-sounding roles - Example day-to-day responsibilities - What a strong portfolio for this role usually shows - Honest caveats on how the title and scope shift by company size, geography, or industry

This is a first draft, written to be reviewed against real practitioner feedback, not a finished, audited reference yet.