feat(pitch-admin): structured form editors, bilingual fields, version preview

Replaces raw JSON textarea in version editor with proper form UIs:

- Company: single-record form with side-by-side DE/EN tagline + mission
- Team: expandable card list with bilingual role/bio, expertise tags
- Financials: year-by-year table with numeric inputs
- Market: TAM/SAM/SOM row table
- Competitors: card list with strengths/weaknesses tag arrays
- Features: card list with DE/EN names + checkbox matrix
- Milestones: card list with DE/EN title/description + status dropdown
- Metrics: card list with DE/EN labels
- Funding: form + nested use_of_funds table
- Products: card list with DE/EN capabilities + feature tag arrays
- FM Scenarios: card list with color picker
- FM Assumptions: row table

Shared editor primitives (components/pitch-admin/editors/):
  BilingualField, FormField, ArrayField, RowTable, CardList

"Edit as JSON" toggle preserved as escape hatch on every tab.

Preview: admin clicks "Preview" on version editor → opens
/pitch-preview/[versionId] in new tab showing the full pitch deck
with that version's data. Admin-cookie gated (no investor auth).
Yellow "PREVIEW MODE" banner at top.

Also fixes the [object Object] inline table type cast in FM editor.

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

pitch-deck/components/PitchDeck.tsx

@@ -47,10 +47,14 @@ interface PitchDeckProps {
   onToggleLanguage: () => void
   investor: Investor | null
   onLogout: () => void
+  previewData?: PitchData | null
 }
 
-export default function PitchDeck({ lang, onToggleLanguage, investor, onLogout }: PitchDeckProps) {
-  const { data, loading, error } = usePitchData()
+export default function PitchDeck({ lang, onToggleLanguage, investor, onLogout, previewData }: PitchDeckProps) {
+  const fetched = usePitchData()
+  const data = previewData || fetched.data
+  const loading = previewData ? false : fetched.loading
+  const error = previewData ? null : fetched.error
   const nav = useSlideNavigation()
   const [fabOpen, setFabOpen] = useState(false)