feat: chatbot rendering provider override and NPI provider ordering

- AI chat extracts 'with provider <name>' and routes claim to that provider
- Claim form reads provider from sessionStorage before any async effects run,
  preventing saved claim/procedure data from overriding the chatbot selection
- NPI provider settings table shows Provider #1 / #2 labels with up/down
  reorder buttons; Provider #1 is always the default for claims
- Default provider now uses sortOrder instead of hardcoded 'Mary Scannell'
- Added sortOrder column to NpiProvider schema with migration

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/Backend/src/ai/internal-chat-workflow.ts

@@ -594,6 +594,7 @@ async function handleClaimOnly(
       serviceDate,
       appointmentId,
       matchedCodes: matched.map((r) => ({ code: r.code!, description: r.description, toothNumber: r.toothNumber, toothSurface: r.toothSurface })),
+      renderingProvider: c.renderingProvider ?? null,
     },
   };
 }