refactor: remove Schattenmarkt from all user-visible UI strings

- Pipeline.tsx: FUTURE_AVAILABILITY label → 'Future Availability'
- ReminderTypeBadge: SCHATTENMARKT_RELEASE label → 'Pre-Market'
- ReminderFilterBar: SCHATTENMARKT_RELEASE label → 'Pre-Market'
- ReminderKpiBar: 'Schattenmarkt-Risiko' → 'Pre-Market Risiko'
- ReminderDetailDrawer: section title + switch label → 'Pre-Market'
- mock-data/matches: explainabilitySummary → 'Pre-Market freigegeben'
- mock-data/reminders: notes → 'Pre-Market Freigabe'

Internal identifiers (schattenmarktRelease field, useSchattenmarktSignals hook,
signal ID prefix schattenmarkt-*) are unchanged — renaming them touches too many
call sites for no user-visible gain.

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

src/components/supply/ReminderKpiBar.tsx

@@ -86,7 +86,7 @@ export function ReminderKpiBar() {
       />
       <KpiItem
         icon={<Eye size={18} color="#be185d" />}
-        label="Schattenmarkt-Risiko"
+        label="Pre-Market Risiko"
         value={insights.schattenmarktReadyCount}
         color="#be185d"
       />