Phase 4 Stage 8: returning-user shell + Tanya Admin sheet

Bestie Choice Sheet on home Mulai Curhat CTA. When the user has at
least one prior session (bestieHistoryHasItemsProvider hits the chat-
sessions history endpoint), the CTA opens a HaloBottomSheet with two
cards: 'bestie yang udah kenal' -> /chat/history, 'bestie baru' ->
/payment/entry. Empty history -> direct to /payment/entry.

Bestie history list visual upgrade: HaloOrb (mitraId seed) + name +
last-session date + topic pills + sessions count + ONLINE pill.
Backend getCustomerHistory now returns topics, mitra_is_online,
sessions_count in a single payload (no per-row presence round-trip).

BestieOfflinePopup with two variants (returning | new_) replacing the
legacy BestieUnavailableDialog. tanya admin ghost CTA on both variants
opens the new TanyaAdminSheet. Stage 5's targeted-wait declined stub
+ Stage 7's chat-screen 409 stub + searching-screen call site all
migrated to the real component.

TanyaAdminSheet: HaloBottomSheet with WA + Telegram buttons, deeplinks
fetched via supportHandlesProvider (CC-config-driven). url_launcher
added to client_app; ios LSApplicationQueriesSchemes covers
https/http/whatsapp/tg.

Stage 2's OTP-blocked popup hubungi admin SnackBar stub also migrated
to TanyaAdminSheet.

Dev-only POST /internal/_test/seed-history-session lets Maestro 08
flow seed a history row before exercising the choice sheet.

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

client_app/.maestro/scripts/seed_history_session.js

@@ -0,0 +1,18 @@
+// Seed a completed chat_sessions row for TEST_PHONE so the bestie history
+// list isn't empty when the Stage 8 flow opens it. Pairs the customer with
+// the most-recently-online mitra in the dev DB.
+//
+// Hits the dev-only /internal/_test/seed-history-session endpoint.
+const phone = TEST_PHONE
+const url = BACKEND_INTERNAL_URL || 'http://localhost:3001'
+const resp = http.post(`${url}/internal/_test/seed-history-session`, {
+  body: JSON.stringify({ phone }),
+  headers: { 'Content-Type': 'application/json' },
+})
+if (resp.status !== 200) {
+  throw new Error(`seed-history-session failed (${resp.status}): ${resp.body}`)
+}
+const data = json(resp.body)
+output.SESSION_ID = data.session_id
+output.MITRA_ID = data.mitra_id
+output.MITRA_NAME = data.mitra_name