docs: rewrite NATS, RabbitMQ, Azure Service Bus, Kafka pages from source; fix SQS and overview
docs: update for FxMap 5.0 (functions replace indexer/filter), add Migration guides, Kafka partitions
docs: remove Previous/Next, Last updated and CTA blocks from wiki pages
docs: import documentation from fxmapper.net (FxMap 4.1.3)