feat: payment PDF extraction, import, and remittance tracking

- Add Upload Payment Documents section with Extract & Download (Excel)
  and Extract & Import (database) buttons
- PDF extractor (pdfplumber) parses MassHealth RA PDFs: two-pass
  strategy joins summary-page ICN/patient map with detail-page
  procedure data (CDT code, paid code, tooth, date, allowed amount)
- RA cover-page summary (Payee ID, RA #, Payment Amount, etc.)
  included as separate Excel sheet; numeric values written as numbers
- Backend PDF import route groups rows by Member #, finds/creates
  patient, creates Payment + ServiceLines with ICN per procedure
- Add icn, paidCode, allowedAmount fields to ServiceLine schema
- Payments table: status simplified to Paid in Full / Balance;
  adjustment auto-computed on mhPaidAmount/copayment change;
  Paid in Full and Revert buttons with confirmation dialogs
- Edit Payment modal: shows ICN, Paid Code, Allowed Amount per line
- PDF Import badge distinguishes from OCR imports in payments table

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

packages/db/generated/prisma/schema.prisma

@@ -242,6 +242,9 @@ model ServiceLine {
   arch          String?
   toothNumber   String?
   toothSurface  String?
+  icn           String?
+  paidCode      String?
+  allowedAmount Decimal?          @db.Decimal(10, 2)
   totalBilled   Decimal           @db.Decimal(10, 2)
   totalPaid     Decimal           @default(0.00) @db.Decimal(10, 2)
   totalAdjusted Decimal           @default(0.00) @db.Decimal(10, 2)