chore(brand): align category to Care Intelligence Platform + npm hygiene (#12)

Coherence sweep across Upstream-family repos surfaced:

1. README intro paragraph and footer both said "Payer intelligence
   Platform" (lowercase 'i', wrong category). Canon per
   _config/BRAND.md and _config/CONSISTENCY.md is "Care Intelligence
   Platform" — established as the category framing on 2026-05-03 and
   used by upstream-skills, upstream-community, and the org profile.
   Fixed both occurrences.

2. package.json description was generic ("MCP server for Upstream
   care intelligence"). Replaced with category-aligned, npm-shopfront
   ready copy. No em dash (forbidden in outbound copy per VOICE.md).

3. Added standard npm registry hygiene fields the published v0.2.0
   package was missing: keywords, author, license (was implicit via
   LICENSE file), homepage, repository, bugs, engines (node >=20 per
   CI), files allowlist. None of these change runtime behavior; they
   surface on npmjs.com/package/@upstream-intelligence/mcp.

4. Added npm version badge to README so release state is visible at
   a glance.

No version bump (coherence sweep, not a release). Build clean, 9/9
tests pass.

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: byteworthy