Remove command-center page and dependencies

The /admin/command-center route was platform_admin-only, used a heavy
custom theme (Major Mono / JetBrains / Inter Tight + ~700 lines of
schematic CSS), called three RPCs, and overlapped with the per-brand
dashboards reachable at /admin, /admin/orders, /admin/stops, and
/admin/reports. The page is being removed; it didn't justify the
build complexity, font payload, or schema surface area.

Changes:
- Drop page, dashboard component, CSS, and server actions
- Remove the platform_admin nav entry from header + sidebar
- Remove the cmd+K palette entry
- Add migration 0042 to drop the 3 RPCs, founder_pain_log table,
  and founder_pain_log_platform view it owned
- Decrement route count in docs/pricing-assessment.md (88 -> 87)

Verification: tsc clean, eslint clean, npm run build clean, command-
center absent from the route list.

docs/pricing-assessment.md

@@ -12,7 +12,7 @@ A **multi-tenant B2B produce distribution platform**, not a SaaS starter. Build
 |---|---|
 | Migrations | **135 SQL files** (production schema, RLS, SECURITY DEFINER RPCs, audit logs) |
 | Source | **544 files** (362 .tsx + 179 .ts) |
-| Admin pages | **88 routes** across orders, products, stops, wholesale, communications, time-tracking, water-log, route-trace, reports, advanced, command-center |
+| Admin pages | **87 routes** across orders, products, stops, wholesale, communications, time-tracking, water-log, route-trace, reports, advanced |
 | API routes | **60+ endpoints** (Stripe + Square + FedEx + Resend + Twilio + 8 AI endpoints) |
 | Public surfaces | 2 brand storefronts (Tuxedo, Indian River Direct) with brand theming, hero, color customization |
 | Integrations | Stripe (Connect + subscriptions), Square (POS sync), FedEx (rates + labels), Resend (email), Twilio (SMS), OpenAI (8 AI tools) |