v2.30.1: Fetcher audit — fix Heroku+Neon, dedup 14 services (523 unique)

What changed

Fetcher fixes (2 broken → working):

• Heroku: Was broken — custom API uses green/yellow/red system status, not Statuspage indicator field. Added heroku fetcher type with proper parser.
• Neon: Was broken — neonstatus.com/api/v2/status.json returns 404. Migrated to status.io API (api.status.io/1.0/status/6878fc85709daa75be6c7e3c). Added statusio fetcher type.

Duplicate deduplication (14 removed):
Eliminated duplicate service entries that inflated count to 537: vercel, cloudflare, netlify, linear, notion (broken notionstatuspage.com URL also removed), resend, clerk, planetscale, launchdarkly, courier, inngest, temporal, gong, lever.

Real unique service count: 523 (was 537 with duplicates, 527 pre-v2.30.0)

Still working (confirmed): Stripe, PagerDuty, AWS, Railway

Tool descriptions updated: refresh_status and README now show 523 (was stale at '141' in README).