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/mock-data/reminders.ts

@@ -193,9 +193,9 @@ export const mockReminders: Reminder[] = [
     currency: 'CHF',
     shadowMarketRisk: ShadowMarketRisk.HIGH,
     schattenmarktEnabled: false,
-    note: 'Objekt noch nicht im Schattenmarkt aktiviert. 14 Monate Lead Time empfohlen.',
+    note: 'Einheit noch nicht für Pre-Market freigegeben. 14 Monate Lead Time empfohlen.',
     activity: [
-      { at: '2026-04-18T10:00:00Z', by: 'Thomas Huber', action: 'CREATED', note: 'Schattenmarkt-Aktivierung ausstehend' },
+      { at: '2026-04-18T10:00:00Z', by: 'Thomas Huber', action: 'CREATED', note: 'Pre-Market-Freigabe ausstehend' },
       { at: '2026-05-02T11:00:00Z', by: 'Thomas Huber', action: 'NOTED', note: 'Eigentümer informiert, Freigabe ausstehend' },
     ],
     organizationId: 'org-wincasa',
@@ -357,7 +357,7 @@ export const mockReminders: Reminder[] = [
     currency: 'CHF',
     shadowMarketRisk: ShadowMarketRisk.HIGH,
     schattenmarktEnabled: false,
-    note: 'Schattenmarkt-Aktivierung 9 Monate vor Vertragsende. Eigentümer-Freigabe einholen.',
+    note: 'Pre-Market Freigabe 9 Monate vor Vertragsende. Eigentümer-Freigabe einholen.',
     activity: [
       { at: '2026-04-25T11:00:00Z', by: 'Anna Meier', action: 'CREATED' },
     ],