feat: create TaskManager singleton class (#3775)

Co-authored-by: dadofsambonzuki <dadofsambonzuki@users.noreply.github.com>

tests/unit/test_pay_invoice.py

@@ -12,15 +12,12 @@ from lnbits.core.crud import create_wallet, get_standalone_payment, get_wallet
 from lnbits.core.crud.payments import get_payment, get_payments_paginated
 from lnbits.core.models import PaymentState, Wallet
 from lnbits.core.services import create_invoice, create_user_account, pay_invoice
-from lnbits.core.services.payments import update_wallet_balance
+from lnbits.core.services.payments import (
+    update_wallet_balance,
+)
 from lnbits.exceptions import InvoiceError, PaymentError
 from lnbits.settings import Settings
-from lnbits.tasks import (
-    create_task,
-    internal_invoice_listener,
-    internal_invoice_queue,
-    wait_for_paid_invoices,
-)
+from lnbits.task_manager import task_manager
 from lnbits.wallets.base import PaymentResponse
 from lnbits.wallets.fake import FakeWallet
 
@@ -237,24 +234,30 @@ async def test_notification_for_internal_payment(
     test_name = "test_notification_for_internal_payment"
 
     # Drain stale items left by session-scoped fixtures (e.g. update_wallet_balance)
-    while not internal_invoice_queue.empty():
+    while not task_manager.internal_invoice_queue.empty():
         try:
-            internal_invoice_queue.get_nowait()
+            task_manager.internal_invoice_queue.get_nowait()
         except asyncio.QueueEmpty:
             break
 
     on_paid_mock = mocker.AsyncMock()
-    create_task(internal_invoice_listener())
-    create_task(wait_for_paid_invoices(test_name, on_paid_mock)())
+    # create_task(internal_invoice_listener())
+
+    task_manager.register_invoice_listener(on_paid_mock, test_name)
+
     payment = await create_invoice(
         wallet_id=to_wallet.id,
         amount=123,
         memo=test_name,
         webhook="http://test.404.lnbits.com",
     )
-    await pay_invoice(
+    paid_payment = await pay_invoice(
         wallet_id=to_wallet.id, payment_request=payment.bolt11, extra={"tag": "lnurlp"}
     )
+    assert paid_payment.status == PaymentState.SUCCESS.value
+    assert paid_payment.bolt11 == payment.bolt11
+    assert paid_payment.amount == -123_000
+
     await asyncio.sleep(1)
 
     assert on_paid_mock.call_count == 1
@@ -264,6 +267,8 @@ async def test_notification_for_internal_payment(
     assert _payment.status == PaymentState.SUCCESS.value
     assert _payment.bolt11 == payment.bolt11
     assert _payment.amount == 123_000
+    assert _payment.checking_id == payment.checking_id
+
     updated_payment = await get_payment(_payment.checking_id)
     assert (
         updated_payment.webhook_status is not None