feat: T6 wave 3 – treatment books from lot, label print lock, restricted zone, authority notices

- Treatments book their dose from a medicine lot (delta booking on edit,
  bulk all-or-nothing, idempotent); Bestandsbuch columns from the lot,
  FEHLT exactly where treatmentLogGaps reports a gap; Bestandsbuch export
  needs veterinary-medicines:read.
- Label printing: 409 LABEL_PARTICULARS_MISSING on gaps, proof print with
  watermark, PRINT audit before the PDF, check endpoints; digit rules only
  from the seeded ComplianceSettings row (fail closed).
- Restricted zone (Berlin day): create, update, move, merge and CSV import
  blocked inside an active restriction; override with reason and
  compliance:manage, audited, never stored on the colony; split, harvest
  and dissolve stay free; restriction details only with compliance:read.
- Authority notices: settings, herd snapshot, registration/herd change/TSK
  notices with one open draft per kind under the settings lock.
- Label check refinements (geometric reading order, number|unit pairs).
- ARCHITECTURE.md §12.6–12.8, Annahmen 71–77; spec §5.6 Berlin day.

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

ApiCore-Backend/src/compliance/tsk-day.ts

@@ -0,0 +1,25 @@
+const MONTH_DAY_PATTERN = /^(\d{2})-(\d{2})$/;
+// Days per month of a non-leap year: 02-29 is not a valid reference day, so
+// the reference day exists in every year.
+const DAYS_IN_MONTH = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31];
+
+/** MM-TT with a real month and a day that exists in a non-leap year. */
+export function isValidMonthDay(value: string): boolean {
+  const match = MONTH_DAY_PATTERN.exec(value);
+  if (!match) {
+    return false;
+  }
+  const month = Number(match[1]);
+  const day = Number(match[2]);
+  return (
+    month >= 1 && month <= 12 && day >= 1 && day <= DAYS_IN_MONTH[month - 1]
+  );
+}
+
+/** The reference day (YYYY-MM-DD) of a year for a stored MM-TT. */
+export function tskReferenceDayOf(year: number, monthDay: string): string {
+  if (!isValidMonthDay(monthDay)) {
+    throw new Error(`Invalid month-day: ${monthDay}`);
+  }
+  return `${String(year).padStart(4, '0')}-${monthDay}`;
+}