Phase 4 checkpoint: chat-screen perf refactor + retryable blast-failure + repo-wide dispose-ref guardrail

Chat-screen performance (customer + mitra):
- Parent screens have zero `ref.watch` — only `ref.listen` for side effects
- Body extracted into its own `ConsumerStatefulWidget`; AppBar parts split
  into narrow `.select` consumers (mode, sensitivity, timer)
- Per-second timer ticks routed to dedicated providers
  (`chatRemainingSecondsProvider` + new `mitraChatRemainingSecondsProvider`)
  so WS `session_tick` frames don't invalidate the rest of the chat state

Dispose-in-ref bug fix:
- `home_screen.dart`, `payment_screen.dart`, `mitra_chat_screen.dart` —
  ref-using cleanup moved from `dispose()` to `deactivate()`. Modern
  Riverpod invalidates `ref` the moment `dispose()` runs; the resulting
  silent error corrupts the widget-tree finalize and the next screen
  appears frozen
- `halo_lints` package added at repo root with `no_ref_in_dispose` rule
  to catch this pattern in CI / IDE analysis
- `custom_lint` activated in both apps' `analysis_options.yaml`
  (was installed but never wired in — also brings `riverpod_lint`'s
  `avoid_ref_inside_state_dispose` online)
- CLAUDE.md Pitfalls section added to client_app + mitra_app

Phase 4 §3 retryable blast-failure (Option A):
- Backend `expirePairingRequest` + all-rejected use
  `recordIntermediateFailure` instead of `failPaymentSession` so the
  payment session stays `confirmed` for re-blast
- WS `pairing_failed` payload carries `is_terminal: false` on the
  retryable paths; client parses the flag and exposes `retryBlast()`
- "Coba cari lagi" CTA on S7 Timeout now re-blasts on the same payment
- Pairing service test updated to reflect the new semantics

Customer waiting-payment screen navigation patch:
- `_navigateTerminal` uses `Future.microtask` + `addPostFrameCallback`
  redundancy after a release-mode bug where polling stopped but
  `context.go` never fired, leaving the screen visually stuck on
  "menunggu pembayaran"

See requirement/resume-2026-05-15.md for next-day pickup checklist
(mitra release rebuild + S21 Ultra install + retest is the gating item).

Bundles unrelated in-flight Phase 4 §2.x work that was already on disk
(ESP screen removal, USP one-time gate scaffolding, bestie-availability
public route, OTP service edits, Maestro flow tweaks) — kept together
to avoid a partial-rebase mess.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

client_app/lib/features/home/providers/bestie_history_provider.dart

@@ -1,5 +1,6 @@
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import '../../../core/api/api_client_provider.dart';
+import '../../../core/auth/auth_notifier.dart';
 
 class BestieHistoryItem {
   final String sessionId;
@@ -28,13 +29,34 @@ class BestieHistoryItem {
       mitraName: json['mitra_display_name'] as String? ?? 'Bestie',
       endedAt: endedAtRaw is String ? DateTime.tryParse(endedAtRaw)?.toLocal() : null,
       topics: (json['topics'] as List?)?.cast<String>() ?? const [],
-      sessionsCount: (json['sessions_count'] as num?)?.toInt() ?? 1,
+      // sessions_count comes from PostgreSQL COUNT(*) which postgres.js
+      // stringifies (bigint precision). Accept both shapes so the factory
+      // doesn't crash when the backend forgets to ::int.
+      sessionsCount: switch (json['sessions_count']) {
+        num n => n.toInt(),
+        String s => int.tryParse(s) ?? 1,
+        _ => 1,
+      },
       mitraIsOnline: json['mitra_is_online'] as bool? ?? false,
     );
   }
 }
 
-final bestieHistoryProvider = FutureProvider<List<BestieHistoryItem>>((ref) async {
+/// Scoped to the current customer so logging in as a different account (or
+/// from anonymous → phone-verified) triggers a refetch instead of returning
+/// the previous customer's cached list. Returns `[]` when no auth — keeps
+/// SHome1st from issuing a doomed 401.
+final bestieHistoryProvider =
+    FutureProvider<List<BestieHistoryItem>>((ref) async {
+  final customerId = ref.watch(authProvider.select((s) {
+    final data = s.valueOrNull;
+    return switch (data) {
+      AuthAuthenticatedData d => d.profile['id'] as String?,
+      AuthAnonymousData d => d.customerId,
+      _ => null,
+    };
+  }));
+  if (customerId == null) return const [];
   final api = ref.read(apiClientProvider);
   final response = await api.get('/api/client/chat/history');
   final items = (response['data']['items'] as List<dynamic>? ?? [])