Bündel 2: Zentrale Helper für DRY-Cleanup, SW by-v1114

NEUE BACKEND-MODULE:

math_utils.py
- haversine_km(lat1, lon1, lat2, lon2) — Distanz in km
- haversine_m(...) — Convenience-Wrapper in Metern
- bbox_deg_from_km(lat, radius_km) — Bounding-Box-Approximation
  für SQL-Vorfilter (statt Haversine im Python-Loop)

config.py
- DB_PATH, MEDIA_DIR, BREEDER_DOCS_DIR, SCANINPUT_DIR
- API_TIMEOUT_SHORT (5s) / DEFAULT (10s) / LONG (30s)
- HTTP_USER_AGENT, HTTP_HEADERS

errors.py
- not_found(msg), forbidden(msg), bad_request(msg), unauthorized(msg)
- conflict(msg), too_many_requests(msg, retry_after), service_unavailable(msg)
- require_or_404(row, msg) — Convenience-Helper

UI.JS ERWEITERUNGEN:

UI.time erweitert:
- formatDate(d)     → "15.03.2026"
- formatDateTime(d) → "15.03.2026, 14:30"
- weekday(d)        → "Di"
- parseISO(str)     → {year, month, day}

UI.text (neu):
- truncate(str, maxLen, ellipsis='…')
- slug(str) — URL-Slug aus String (mit DE-Umlauten)

UI.money (neu):
- format(value) → "12,34 €" (de-DE, EUR)
- formatWithSuffix(value, '/Jahr')

HAVERSINE-MIGRATION (13 Backend-Routen):
alerts.py, services.py, places.py, events.py, diary.py, playdate.py,
lost.py, poison.py, adoption.py, gassi_zeiten.py, sitting.py, routen.py,
walks.py

- Alle lokalen def _haversine/haversine_km entfernt
- Aufrufe ersetzt durch haversine_km/haversine_m je nach Einheit
- from math_utils import haversine_km|haversine_m in jeder Datei

Tests 19/19 grün.

Hinweis: Migrationen für MEDIA_DIR (19 Stellen), API-Timeouts (12),
Date-Formatter im Frontend (24) und UI.text.truncate (5) sind als
Folge-Sprints möglich. Helper sind verfügbar.

backend/static/js/ui.js

@@ -490,13 +490,73 @@ const UI = (() => {
       return fmtDate.format(new Date(dateStr));
     }
 
+    // Datum: "15.03.2026" / "15.03.2026, 14:30"
+    const _fmtDateNumeric = new Intl.DateTimeFormat('de-DE', {
+      day: '2-digit', month: '2-digit', year: 'numeric'
+    });
+    const _fmtDateTimeNumeric = new Intl.DateTimeFormat('de-DE', {
+      day: '2-digit', month: '2-digit', year: 'numeric',
+      hour: '2-digit', minute: '2-digit'
+    });
+    // Wochentag: "Di." / Tag im Monat: "15"
+    const _fmtWeekday = new Intl.DateTimeFormat('de-DE', { weekday: 'short' });
+
     return {
       relative,
-      format:      d => fmtDate.format(new Date(d)),
-      formatShort: d => fmtDateShort.format(new Date(d)),
+      format:        d => fmtDate.format(new Date(d)),
+      formatShort:   d => fmtDateShort.format(new Date(d)),
+      formatDate:    d => _fmtDateNumeric.format(new Date(d)),         // 15.03.2026
+      formatDateTime:d => _fmtDateTimeNumeric.format(new Date(d)),     // 15.03.2026, 14:30
+      weekday:       d => _fmtWeekday.format(new Date(d)).replace('.', ''),
+      // ISO-Parser: "2026-03-15" → { year, month, day }
+      parseISO(str) {
+        if (!str) return null;
+        const m = String(str).match(/^(\d{4})-(\d{2})-(\d{2})/);
+        return m ? { year: +m[1], month: +m[2], day: +m[3] } : null;
+      },
     };
   })();
 
+  // ----------------------------------------------------------
+  // TEXT — String-Helper
+  // ----------------------------------------------------------
+  const text = {
+    /** Schneidet str auf maxLen ab und hängt ellipsis an. */
+    truncate(str, maxLen = 80, ellipsis = '…') {
+      if (!str) return '';
+      const s = String(str);
+      return s.length <= maxLen ? s : s.slice(0, maxLen - ellipsis.length) + ellipsis;
+    },
+    /** Slug aus String — für URL-Pfade. */
+    slug(str) {
+      return String(str || '')
+        .toLowerCase()
+        .replace(/ä/g, 'ae').replace(/ö/g, 'oe').replace(/ü/g, 'ue').replace(/ß/g, 'ss')
+        .replace(/[^a-z0-9]+/g, '-')
+        .replace(/(^-|-$)/g, '');
+    },
+  };
+
+  // ----------------------------------------------------------
+  // MONEY — Currency-Formatierung (de-DE, EUR)
+  // ----------------------------------------------------------
+  const _fmtEur = new Intl.NumberFormat('de-DE', {
+    style: 'currency', currency: 'EUR',
+    minimumFractionDigits: 2, maximumFractionDigits: 2,
+  });
+  const money = {
+    /** Formatiert Zahl als "12,34 €" — null/undefined ergibt "—". */
+    format(value) {
+      if (value == null || value === '' || isNaN(value)) return '—';
+      return _fmtEur.format(Number(value));
+    },
+    /** Mit Suffix wie "/Jahr". */
+    formatWithSuffix(value, suffix = '') {
+      if (value == null || value === '' || isNaN(value)) return '—';
+      return _fmtEur.format(Number(value)) + (suffix ? ' ' + suffix : '');
+    },
+  };
+
   // ----------------------------------------------------------
   // FOTO-VORSCHAU (Input[type=file] → img)
   // ----------------------------------------------------------
@@ -1272,7 +1332,7 @@ const UI = (() => {
     toast, modal,
     setLoading, asyncButton,
     formData, setFormError, clearFormErrors,
-    emptyState, errorState, time,
+    emptyState, errorState, time, text, money,
     previewUrl, previewFallback,
     setupPhotoPreview, scrollTop, skeleton, skeletonList,
     moneyInput, parseMoney, datePicker,