fix: reduce reconnect backoff to 1s flat

Exponential backoff up to 300s made no sense with rotating Tor exits
where each reconnect gets a fresh IP. Single 1s delay is sufficient.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

tests/test_config.py

@@ -151,7 +151,7 @@ channel_keys = { "#secret" = "hunter2" }
         cfg = load(_write_config(MINIMAL_CONFIG))
         b = cfg.bouncer
         assert b.probation_seconds == 45
-        assert b.backoff_steps == [5, 10, 30, 60, 120, 300]
+        assert b.backoff_steps == [1]
         assert b.nick_timeout == 10
         assert b.rejoin_delay == 3
         assert b.http_timeout == 15