Check the four integration nodes under strict mypy

mqtt, http, influx and delay carried the prototype's annotations and were
excluded wholesale. Annotating them leaves nothing to exclude: what the two
untyped dependencies need is an implicit-reexport allowance for
influxdb_client and the import-site ignore croniter already gets elsewhere.

InfluxDbNode.inject now takes the durable flag its supertype passes, and the
cron loop reads its stop event once instead of dereferencing a field that
stop_cron() may have cleared.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01H7LwYgJfpkbLCTeiAf8U4A

backend/pyproject.toml

@@ -46,18 +46,17 @@ build-backend = "hatchling.build"
 [tool.mypy]
 strict = true
 exclude = ["venv", ".venv", "alembic"]
+# influxdb_client's Point builder carries no annotations; calling it is not a
+# reason to stop checking the caller (app/flow/nodes/influx.py).
+untyped_calls_exclude = ["influxdb_client"]
 
-# The integration nodes still carry the prototype's annotations, and croniter and
-# influxdb_client ship no stubs. Shrinking one module at a time as each integration
-# is revisited; the rest of the package, and everything around it, is checked strictly.
+# Every module is checked strictly. influxdb_client is typed but re-exports its
+# names implicitly, which strict mode refuses to follow. (croniter, the other
+# untyped dependency, is ignored at its two import sites.)
 [[tool.mypy.overrides]]
-module = [
-    "app.flow.nodes.delay",
-    "app.flow.nodes.http",
-    "app.flow.nodes.influx",
-    "app.flow.nodes.mqtt",
-]
-ignore_errors = true
+module = ["influxdb_client"]
+implicit_reexport = true
+
 
 [tool.ruff]
 target-version = "py310"