feat(export): Bestandsbuch für Tierarzneimittel nach Art. 108 VO (EU) 2019/6

- Treatment records supplier, purchase proof and prescribing vet, and
  keeps the apiary the colony stood at on the treatment day.
- Holder name and address in site settings (never in public output;
  regression test in public.service.spec).
- treatment-log.pdf: one sheet per apiary, identical treatments grouped,
  missing mandatory fields printed as FEHLT, uncertain locations marked.
- Shared PDF table helpers extracted from the record card.

Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>

ApiCore-Backend/src/export/pdf-table.ts

@@ -0,0 +1,107 @@
+/**
+ * Small pdfkit helpers shared by the printable records (Stockkarte,
+ * Bestandsbuch): dates, empty values and a table that repeats its header on
+ * every page.
+ */
+
+export const PDF_MARGIN = 36;
+
+export interface PdfColumn {
+  header: string;
+  width: number;
+}
+
+export function formatDay(date: Date): string {
+  return date.toLocaleDateString('de-DE', {
+    day: '2-digit',
+    month: '2-digit',
+    year: 'numeric',
+    timeZone: 'UTC',
+  });
+}
+
+export function orDash(value: string | number | null | undefined): string {
+  return value === null || value === undefined || value === ''
+    ? '–'
+    : String(value);
+}
+
+/** Widens the last column so the table fills the page width. */
+export function fillWidth(
+  doc: PDFKit.PDFDocument,
+  columns: PdfColumn[],
+): PdfColumn[] {
+  const fixed = columns.slice(0, -1).reduce((sum, c) => sum + c.width, 0);
+  const last = columns[columns.length - 1];
+  return [
+    ...columns.slice(0, -1),
+    { ...last, width: doc.page.width - 2 * PDF_MARGIN - fixed },
+  ];
+}
+
+export function drawSection(doc: PDFKit.PDFDocument, title: string): void {
+  if (doc.y > doc.page.height - PDF_MARGIN - 80) doc.addPage();
+  doc.moveDown(0.6);
+  doc
+    .font('Helvetica-Bold')
+    .fontSize(11)
+    .fillColor('#000000')
+    .text(title, PDF_MARGIN);
+  doc.moveDown(0.2);
+}
+
+/** Draws a simple table, repeating the header on every new page. */
+export function drawTable(
+  doc: PDFKit.PDFDocument,
+  columns: PdfColumn[],
+  rows: string[][],
+): void {
+  const left = PDF_MARGIN;
+  const bottomLimit = doc.page.height - PDF_MARGIN - 20;
+
+  const drawRow = (cells: string[], bold: boolean) => {
+    doc.font(bold ? 'Helvetica-Bold' : 'Helvetica').fontSize(8);
+    const heights = cells.map((cell, index) =>
+      doc.heightOfString(cell, { width: columns[index].width - 4 }),
+    );
+    const rowHeight = Math.max(...heights, 10) + 4;
+    if (doc.y + rowHeight > bottomLimit) {
+      doc.addPage();
+      if (!bold) {
+        drawRow(
+          columns.map((c) => c.header),
+          true,
+        );
+        doc.font('Helvetica').fontSize(8);
+      }
+    }
+    const top = doc.y;
+    let x = left;
+    cells.forEach((cell, index) => {
+      doc.text(cell, x + 2, top + 2, { width: columns[index].width - 4 });
+      x += columns[index].width;
+    });
+    doc
+      .moveTo(left, top + rowHeight)
+      .lineTo(x, top + rowHeight)
+      .lineWidth(0.3)
+      .strokeColor('#999999')
+      .stroke();
+    doc.y = top + rowHeight;
+  };
+
+  drawRow(
+    columns.map((c) => c.header),
+    true,
+  );
+  if (rows.length === 0) {
+    doc
+      .font('Helvetica-Oblique')
+      .fontSize(8)
+      .text('Keine Einträge.', left + 2, doc.y + 2);
+    doc.moveDown(0.5);
+    return;
+  }
+  for (const row of rows) drawRow(row, false);
+  doc.moveDown(0.5);
+}