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>

apps/Backend/src/services/paymentService.ts

@@ -176,6 +176,154 @@ export async function updatePayment(
 
 // handling full-ocr-payments-import
 
+// ── helpers shared by the PDF import ──────────────────────────────────────────
+
+function parsePdfDate(dateStr: string): Date {
+  // "MM/DD/YY" → Date UTC
+  if (!dateStr) return new Date();
+  const parts = dateStr.split("/");
+  if (parts.length !== 3) return new Date();
+  const month = parseInt(parts[0]!, 10) - 1;
+  const day   = parseInt(parts[1]!, 10);
+  const year  = 2000 + parseInt(parts[2]!, 10);
+  return new Date(Date.UTC(year, month, day));
+}
+
+function parseTooth(tooth: string): { toothNumber: string | null; toothSurface: string | null } {
+  if (!tooth?.trim()) return { toothNumber: null, toothSurface: null };
+  const parts = tooth.trim().split(/\s+/);
+  return {
+    toothNumber:  parts[0] || null,
+    toothSurface: parts.slice(1).join(" ") || null,
+  };
+}
+
+function parsePdfName(fullName: string): { firstName: string; lastName: string } {
+  // "LAST, FIRST" or "LAST LAST, FIRST"
+  const commaIdx = fullName.indexOf(", ");
+  if (commaIdx === -1) return { firstName: fullName, lastName: "Unknown" };
+  return {
+    lastName:  fullName.slice(0, commaIdx).trim(),
+    firstName: fullName.slice(commaIdx + 2).trim(),
+  };
+}
+
+export type PdfRow = {
+  "Patient Name":     string;
+  "Member #":         string;
+  "ICN":              string;
+  "Submitted Code":   string;
+  "Paid Code":        string;
+  "Tooth":            string;
+  "Date of Service":  string;
+  "Submitted Amount": string;
+  "Allowed Amount":   string;
+  "Paid Amount":      string;
+  "Source File":      string;
+};
+
+export const pdfImportService = {
+  async importRows(rows: PdfRow[], userId: number) {
+    // Group by Member # — one payment per patient
+    const byMember = new Map<string, PdfRow[]>();
+    for (const row of rows) {
+      const key = row["Member #"] || row["Patient Name"];
+      if (!byMember.has(key)) byMember.set(key, []);
+      byMember.get(key)!.push(row);
+    }
+
+    const paymentIds: number[] = [];
+
+    for (const [, patientRows] of byMember) {
+      const first = patientRows[0]!;
+      const memberNo   = first["Member #"];
+      const patientName = first["Patient Name"];
+
+      const totalBilled = patientRows.reduce(
+        (s, r) => s.plus(new Decimal(r["Submitted Amount"] || 0)),
+        new Decimal(0)
+      );
+      const totalMhPaid = patientRows.reduce(
+        (s, r) => s.plus(new Decimal(r["Paid Amount"] || 0)),
+        new Decimal(0)
+      );
+      const adjustment = Decimal.max(0, totalBilled.minus(totalMhPaid));
+
+      const paymentId = await prisma.$transaction(async (tx: typeof prisma) => {
+        // 1. Find or create patient
+        let patient = memberNo
+          ? await tx.patient.findFirst({ where: { insuranceId: memberNo } })
+          : null;
+
+        if (!patient) {
+          const { firstName, lastName } = parsePdfName(patientName);
+          patient = await tx.patient.create({
+            data: {
+              firstName,
+              lastName,
+              insuranceId: memberNo || null,
+              dateOfBirth: new Date(Date.UTC(1900, 0, 1)),
+              gender: "",
+              phone: "",
+              userId,
+            },
+          });
+        }
+
+        // 2. Create payment
+        const payment = await tx.payment.create({
+          data: {
+            patientId:    patient.id,
+            userId,
+            totalBilled,
+            totalPaid:    new Decimal(0),
+            totalAdjusted: new Decimal(0),
+            totalDue:     totalBilled,
+            mhPaidAmount: totalMhPaid,
+            adjustment,
+            status:  "PENDING",
+            notes:   `PDF import from ${first["Source File"] ?? "unknown file"}`,
+          },
+        });
+
+        // 3. Create one service line per row
+        for (const row of patientRows) {
+          const billed = new Decimal(row["Submitted Amount"] || 0);
+          const mhPaid = new Decimal(row["Paid Amount"]      || 0);
+          const due    = Decimal.max(0, billed.minus(mhPaid));
+          const { toothNumber, toothSurface } = parseTooth(row["Tooth"]);
+
+          const allowed = new Decimal(row["Allowed Amount"] || 0);
+
+          await tx.serviceLine.create({
+            data: {
+              paymentId:     payment.id,
+              icn:           row["ICN"]            || null,
+              procedureCode: row["Submitted Code"] || "",
+              paidCode:      row["Paid Code"]      || null,
+              allowedAmount: allowed,
+              toothNumber,
+              toothSurface,
+              procedureDate: parsePdfDate(row["Date of Service"]),
+              totalBilled:   billed,
+              totalPaid:     mhPaid,
+              totalAdjusted: new Decimal(0),
+              totalDue:      due,
+              status:        mhPaid.gt(0) ? "PARTIALLY_PAID" : "UNPAID",
+            },
+          });
+        }
+
+        return payment.id;
+      });
+
+      paymentIds.push(paymentId);
+    }
+
+    return paymentIds;
+  },
+};
+
 export const fullOcrPaymentService = {
   async importRows(rows: OcrRow[], userId: number) {
     const results: number[] = [];