fix(dkv): handle EV charging rows and service rows in single-tx tab parser

Analyzed Invoice-4302486921-26_650869002_000.pdf text structure. Three cases:

1. FUEL (fields[4] = numeric tx-nr): km+product merged in fields[5], unit in
   fields[6]. Already working; no change.

2. EV CHARGING (fields contains "DDDD KWH" or "DDDD MIN" unit): column layout
   shifts — no km field, station+ort sometimes merged in fields[1]. Detected by
   regex on unit field; kwhIdx drives relative offset for menge/netto/brutto.
   Ort extracted from fields[2] (kwhIdx>=5) or fields[1] (kwhIdx=4, compact).
   Kilometerstand = 0 (EV chargers don't record odometer).

3. SERVICE ROWS (e.g. "DKV Analytics Premiu"): appear inside a VEHICLE: block but
   fields[4] is non-numeric (product description, not a transaction number). These
   were being parsed as fake vehicle transactions producing wrong ort/km values.
   Now filtered out (return null).

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

apps/api/src/dkv/dkv-parser.service.ts

@@ -115,21 +115,31 @@ export class DkvParserService {
 
   // ─── Private: Single-transaction tab-separated line ────────────────────────
   //
-  // DKV single-tx tab format (empirically verified against invoice.pdf):
+  // DKV produces two distinct single-tx tab formats:
   //
+  // FUEL format:
   //   [0]  Lieferdatum      DD.MM.YYYY
   //   [1]  Station Name     e.g. "ESSO"
   //   [2]  Ort              e.g. "DONZDORF"
   //   [3]  Servicest.-Nr    e.g. "0071132"
-  //   [4]  Transaktions-Nr  e.g. "189945"
-  //   [5]  "KM PRODUKT"     e.g. "68040 DIESEL" (km and product merged, no tab between)
+  //   [4]  Transaktions-Nr  e.g. "189945"  ← purely numeric
+  //   [5]  "KM PRODUKT"     e.g. "68040 DIESEL" (km and product merged)
+  //                         or just PRODUKT when driver did not enter km
   //   [6]  "CODE UNIT"      e.g. "0009 LTR"
   //   [7]  Menge            e.g. "45,910"
-  //   [8]  Preis/E brutto   e.g. "2,1790"
-  //   [9]  Preis/E netto    e.g. "1,8312"
-  //   [10] Bezugswert brutto e.g. "100,04"
-  //   [11] Bezugswert netto  e.g. "84,07"
-  //   ...
+  //   [10] Bezugswert brutto
+  //   [11] Bezugswert netto
+  //
+  // EV CHARGING format — detected by "DDDD KWH" unit field:
+  //   kwhIdx=5 (standard EV, station and ort separate):
+  //     [1] Station Name, [2] Ort, [3] Charge Point ID,
+  //     [4] Produkt, [5] "0964 KWH", [6] Menge, [9] netto, [12] brutto
+  //   kwhIdx=4 (compact EV, station+ort merged into [1]):
+  //     [1] "Name ORT" merged, [2] Charge Point ID,
+  //     [3] Produkt, [4] "0963 KWH", [5] Menge, [8] netto, [11] brutto
+  //
+  // SERVICE ROWS (e.g. "DKV Analytics Premiu") appear inside a VEHICLE: block but
+  // are not vehicle transactions — detected by non-numeric fields[4] → skip.
 
   private parseSingleTxLine(line: string): DkvTransaction | null {
     const fields = line.split('\t').map(f => f.trim());
@@ -138,7 +148,31 @@ export class DkvParserService {
     const datePattern = /^\d{2}\.\d{2}\.\d{4}$/;
     if (!datePattern.test(fields[0])) return null;
 
-    // fields[5] = "KM_VALUE PRODUKT" — split on first whitespace boundary
+    // Detect EV charging: look for a unit field matching "DDDD KWH" or "DDDD MIN"
+    const kwhIdx = fields.findIndex(f => /^\d{4}\s+(KWH|MIN)$/i.test(f));
+    if (kwhIdx !== -1) {
+      // kwhIdx=5: ort is separate in fields[2]; kwhIdx=4: station+ort merged in fields[1]
+      const ort = kwhIdx >= 5 ? (fields[2] ?? '') : (fields[1] ?? '');
+      const mengeIdx = kwhIdx + 1;
+      const nettoIdx = kwhIdx + 3;
+      const bruttoIdx = kwhIdx + 6;
+      return {
+        lieferdatum: fields[0],
+        ort,
+        kilometerstand: 0,
+        produkt: fields[kwhIdx - 1] ?? '',
+        menge: parseDE(fields[mengeIdx] || '0'),
+        einheit: fields[kwhIdx]?.split(/\s+/)[1] ?? 'KWH',
+        netto: parseDE(fields[nettoIdx] || '0'),
+        brutto: parseDE(fields[bruttoIdx] || '0'),
+      };
+    }
+
+    // Standard fuel rows: fields[4] must be a numeric transaction number.
+    // Non-numeric field[4] = service charge row (e.g. DKV Analytics fee) → skip.
+    if (!/^\d+$/.test(fields[4] ?? '')) return null;
+
+    // fields[5] = "KM PRODUKT" merged, or just PRODUKT when driver skipped km entry
     const kmAndProdukt = fields[5].split(/\s+/);
     const km = kmAndProdukt[0] ?? '0';
     const produkt = kmAndProdukt.slice(1).join(' ');
@@ -152,10 +186,10 @@ export class DkvParserService {
       ort: fields[2] ?? '',
       kilometerstand: parseDE(km),
       produkt,
-      menge: parseDE(fields[7] ?? '0'),
+      menge: parseDE(fields[7] || '0'),
       einheit,
-      netto: parseDE(fields[11] ?? '0'),
-      brutto: parseDE(fields[10] ?? '0'),
+      netto: parseDE(fields[11] || '0'),
+      brutto: parseDE(fields[10] || '0'),
     };
   }