feat(share): add Share Collection cashier flow and fix Share Product accounting

- Add Share Collection screen under Cashier menu for cash pre-collection
  before share account activation; posts Dr Cash Vault, Cr Share Sundry,
  Cr Income GL entries with duplicate-collection guard
- Restore all 4 GL mappings (Assets, Liabilities, Income, Equity) in Share
  Product accounting step with pill-style savings-product UI
- Remove Multiples section from Share Product currency step; default
  Decimal Places to 2
- GET /cashier/sharecollection/:id endpoint for collection status check

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

src/app/cashier/cashier.service.ts

@@ -156,4 +156,22 @@ export class CashierService {
     if (asOfDate) params = params.set('asOfDate', asOfDate);
     return this.http.get('/cashreconciliation/expected/me', { params });
   }
+
+  // ── Payment Types ──
+  getPaymentTypes(): Observable<any[]> {
+    return this.http.get<any[]>('/paymenttypes');
+  }
+
+  // ── Share Collection ──
+  getShareAccountForCollection(accountId: string): Observable<any> {
+    return this.http.get(`/accounts/share/${accountId}`);
+  }
+
+  collectSharePayment(data: any): Observable<any> {
+    return this.http.post('/cashier/sharecollection', data);
+  }
+
+  getShareCollectionStatus(shareAccountId: number): Observable<any> {
+    return this.http.get(`/cashier/sharecollection/${shareAccountId}`);
+  }
 }