Discoverability: npm keywords, GitHub metadata and README above the fold #256

The library doesn't appear in search results for "typescript saga", "nservicebus node" or "node service bus".

• Add npm keywords to every package: saga, workflow, outbox, process-manager, sqs, sns, rabbitmq, pub-sub, cqrs, event-driven, masstransit, nservicebus. Use third-party names only as descriptive keywords, never in package names, descriptions or branding.

• Rewrite the GitHub description. The current one is "enterprise service bus ... enterprise integration patterns", which few people search for. Update the topics to match.

• Root README: a one-line pitch, a roughly 20-line runnable example above the fold, a feature list, badges (npm, CI, downloads) and a link to the tutorial.

• Write a launch post on dev.to or the blog once the Phase 1 and Phase 2 items are done.

• Add a short trademark/non-affiliation notice to the root README footer.