fix(pitch-deck): remove Sonst. Erträge tab + add investments

- Removed 'sonst_ertraege' from SHEET_LIST (empty, irrelevant for pre-seed)
- DB: Added Mac Studio (LLM Training) 13.000 EUR, Jan 2027, AfA 3 Jahre
- DB: Added Software-Lizenzen (GWG) 800 EUR/Jahr (2026-2030)
- DB: Added Domain/SSL/Zertifikate (GWG) 500 EUR at founding
- DB: Removed GPU-Server (wrong assumption — Mac Studio used instead)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

pitch-deck/lib/finanzplan/types.ts

@@ -204,7 +204,6 @@ export const SHEET_LIST: SheetMeta[] = [
   { name: 'personalkosten', label_de: 'Personalkosten', label_en: 'Personnel', rows: 0, editable_rows: 0 },
   { name: 'betriebliche', label_de: 'Betriebliche Aufwendungen', label_en: 'Operating Expenses', rows: 0, editable_rows: 0 },
   { name: 'investitionen', label_de: 'Investitionen', label_en: 'Investments', rows: 0, editable_rows: 0 },
-  { name: 'sonst_ertraege', label_de: 'Sonst. Ertraege', label_en: 'Other Income', rows: 0, editable_rows: 0 },
   { name: 'liquiditaet', label_de: 'Liquiditaet', label_en: 'Cash Flow', rows: 0, editable_rows: 0 },
   { name: 'guv', label_de: 'GuV', label_en: 'P&L', rows: 0, editable_rows: 0 },
 ]