scaffold tasks extension

Empty skeleton mirroring the events extension layout: config/manifest,
pyproject + Makefile + ruff/mypy config, FastAPI routers wired into
tasks_ext, NostrClient bootstrap stubs, and an empty static/routes.json.

Models, migrations, CRUD, Nostr publisher/sync, and the API/template
layers land in follow-up commits.

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

views.py

@@ -0,0 +1,16 @@
+from fastapi import APIRouter, Depends
+from lnbits.core.views.generic import index, index_public
+from lnbits.decorators import check_account_id_exists
+
+tasks_generic_router = APIRouter()
+
+tasks_generic_router.add_api_route(
+    "/",
+    methods=["GET"],
+    endpoint=index,
+    dependencies=[Depends(check_account_id_exists)],
+)
+
+tasks_generic_router.add_api_route(
+    "/{task_id}", methods=["GET"], endpoint=index_public
+)