loadBpmDetective cached the promise returned by dynamic import even when
that import rejected. A transient failure (network hiccup, bundler issue,
missing module at first access) was therefore cached as null for the rest
of the session, silently disabling BPM detection.
- Reset the cached promise on import failure so the next call retries.
- Only cache the default production import; custom loaders bypass the cache.
- Make loadBpmDetective testable by accepting an optional importFn.
- Add regression tests for failure/retry and module/default resolution.
Santhi Prakash
b4bd670402