Previously, _stop_adapter() used pop() to remove adapter state,
which lost last_completed_poll. On re-enable, a fresh state was
created, causing immediate poll and violating rate-limit guarantee.
Changes:
- Add is_running property to AdapterState
- _stop_adapter: preserve state, just cancel task
- _start_adapter: reuse existing stopped state if present
- Add _remove_adapter for full cleanup when adapter is deleted
- _on_config_change: call _remove_adapter for deleted adapters
Integration tests verify:
- Test A: gap > cadence -> immediate poll (correct)
- Test B: gap < cadence -> wait until last_poll + cadence (was broken)
- Test C: delete + re-add -> fresh state (correct)
Tests-fail-before-fix verified: Test A/B failed on unfixed code
with "State was removed on stop!", pass with fix.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
