feat(clearing): add CTS/NACH clearing UI with real NPCI batch sessions

- CTS clearing module: inward batches (validate/pass/return), outward presentment
  capture, positive pay, settlement, reconciliation
- Outward Clearing merged into one screen: Pending Cheques + Batches tabs (a real
  clearing session per NPCI submission, either the 2-hourly job or manual send),
  drill into a batch to settle/dishonour its cheques
- Date-range, text, and quick (Today/Yesterday/All) filters with pagination across
  inward batches, outward presentments, outward batches, and batch detail
- NACH clearing module (mandates, batches, transaction decisioning)
- Shell/sidenav wiring for both new modules

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/app/clearing-network/clearing.service.ts

@@ -0,0 +1,77 @@
+/**
+ * Copyright since 2025 Mifos Initiative
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+/** Angular Imports */
+import { Injectable, inject } from '@angular/core';
+import { HttpClient, HttpParams } from '@angular/common/http';
+import { Observable } from 'rxjs';
+
+/**
+ * Shared clearing services used across CTS and NACH — return-reason-code master, settlement-batch posting,
+ * and reconciliation.
+ */
+@Injectable({
+  providedIn: 'root'
+})
+export class ClearingService {
+  private http = inject(HttpClient);
+
+  // ----- Return reason codes -----
+
+  /** appliesTo: 'CTS' | 'NACH'. Returns a raw array of reason codes. */
+  getReturnReasonCodes(appliesTo: string): Observable<any> {
+    return this.http.get('/clearing/return-reason-codes', {
+      params: new HttpParams().set('appliesTo', appliesTo)
+    });
+  }
+
+  // ----- Settlement batches -----
+
+  /** Server-side paginated — returns { pageItems, totalFilteredRecords }. */
+  getSettlementBatches(clearingType?: string, status?: string, offset = 0, limit = 20): Observable<any> {
+    let params = new HttpParams().set('offset', offset).set('limit', limit);
+    if (clearingType) params = params.set('clearingType', clearingType);
+    if (status) params = params.set('status', status);
+    return this.http.get('/clearing/settlement-batches', { params });
+  }
+
+  getSettlementBatch(id: string | number): Observable<any> {
+    return this.http.get(`/clearing/settlement-batches/${id}`);
+  }
+
+  /** payload: { clearingType, sourceBatchId }. */
+  prepareSettlement(payload: any): Observable<any> {
+    return this.http.post('/clearing/settlement-batches', payload);
+  }
+
+  postSettlement(id: string | number): Observable<any> {
+    return this.http.post(
+      `/clearing/settlement-batches/${id}`,
+      {},
+      { params: new HttpParams().set('command', 'post') }
+    );
+  }
+
+  rejectSettlement(id: string | number, payload: any): Observable<any> {
+    return this.http.post(`/clearing/settlement-batches/${id}`, payload, {
+      params: new HttpParams().set('command', 'reject')
+    });
+  }
+
+  // ----- Reconciliations -----
+
+  getReconciliations(clearingType?: string, offset = 0, limit = 20): Observable<any> {
+    let params = new HttpParams().set('offset', offset).set('limit', limit);
+    if (clearingType) params = params.set('clearingType', clearingType);
+    return this.http.get('/clearing/reconciliations', { params });
+  }
+
+  runReconciliation(payload: any): Observable<any> {
+    return this.http.post('/clearing/reconciliations', payload);
+  }
+}