v1.4.1: per-run summary log (feeds/evaluated/selected/filtered/failed)

- _broadcast checks match filter and returns (placed, filtered, failed)
- _poll_once accumulates per-run counters, logs one summary line per run
- run_log_file config writes to /data/buzzrss-runs.log (persistent mount)
- _poll_feeds re-raises CancelledError so reloads stop old poll loops
- _setup_run_log fully resets handlers; empty config disables logging

maubot.yaml

@@ -1,5 +1,5 @@
 id: nl.eddydevink.rss
-version: 1.3.1
+version: 1.4.1
 modules:
 - buzzrss
 main_class: RSSBot