fix: update Pollinations text requests

[voodoohop]

• Fixes malformed Pollinations simplified-text URLs in SimpleCite and SimpleSuite.
• Moves publishable-key authentication from URL parameters to the Authorization header.
• Requests JSON only where structured citation output is expected and reports non-2xx API errors.

Validation:

• npm run build
• git diff --check

The existing lockfile is out of sync with package.json; this PR leaves that unrelated dependency state unchanged.