fix: remove KFZ formula rows from engine (now manual from Jan 2028)

pitch-deck/lib/finanzplan/engine.ts

@@ -254,9 +254,7 @@ export async function computeFinanzplan(pool: Pool, scenarioId: string): Promise
   // Formula-based rows: derive from headcount (excl. founders) or customers
   const formulaRows: { label: string; perUnit: number; source: MonthlyValues }[] = [
     { label: 'Fort-/Weiterbildungskosten (F)', perUnit: 300, source: hcWithoutFounders },
-    { label: 'Fahrzeugkosten (F)', perUnit: 200, source: hcWithoutFounders },
-    { label: 'KFZ-Steuern (F)', perUnit: 25, source: hcWithoutFounders },
-    { label: 'KFZ-Versicherung (F)', perUnit: 150, source: hcWithoutFounders },
+    // KFZ costs are manual (from Jan 2028), not formula-based
     { label: 'Reisekosten (F)', perUnit: 75, source: headcount },
     { label: 'Bewirtungskosten (F)', perUnit: 50, source: totalBestandskunden },
     { label: 'Internet/Mobilfunk (F)', perUnit: 50, source: headcount },