- test_plugins.py: remove tests for unimplemented plugin command API
(get_plugin_command_handler, register_command never existed)
- test_redact.py: add autouse fixture to clear HERMES_REDACT_SECRETS
env var leaked by cli.py import in other tests
- test_signal.py: same HERMES_REDACT_SECRETS fix for phone redaction
- test_mattermost.py: add @bot_user_id to test messages after the
mention-only filter was added in #2443
- test_context_token_tracking.py: mock resolve_provider_client for
openai-codex provider that requires real OAuth credentials
Full suite: 5893 passed, 0 failed.