* remove --mode from the CLI
* move WakuMode to the messaging layer
* expose store backend (db url, max connections) and a remote store node on the messaging surface
* wakunode2 with no flags now runs as a full service node (store still opt-in)
* add rateLimitMessagesPerEpoch
* channel rate-limiting auto-enables if epochPeriodSec or messagesPerEpoch is set
* fix JSON conf parser to be generic (works over all config types)
* messaging config = mode + preset + messagingOverrides + channelsOverrides
* add full messaging plus selective kernel config options to MessagingClientConf
* mode (Core/Edge) expands to kernel protocol flags in the messaging layer
* create_node parses the messaging config, drops the flat WakuNodeConf JSON entrypoint
* wire channelsOverrides (segmentation/SDS/rate-limit) into channel creation
* fix liblogosdelivery.h comments and README for the new config shape
* messaging conf tests: switch names, reject-unknown, set-twice, field->kernel
* add kernel log-level, log-format, nodekey to the messaging surface
* Port 0 (ephemeral) default for messaging entry points
* KernelConf alias for WakuNodeConf
* rewrite the FFI examples to the new config shape
* C/C++ examples use preset status.prod
* drop operator-only confs from the examples
* remove duplicate tests & misc test fixes
* Delete p2pReliability from Kernel (Waku) resolver and config (keep preset definition)
* Delete NodeConfig API (deprecation completed by p2pReliability removal from kernel)
* Rename test_messaging_conf.nim to test_conf.nim (tests Logos Delivery config in general)
* Rename messaging_conf_json.nim to logos_delivery_conf_json.nim
* Add logos_delivery_conf.nim (defines LogosDeliveryConf aggregate)
* misc docs/comments cleanups
* deep changes in libwaku to adap to nim-ffi
* start using ffi pragma in library
* update some binding examples
* add missing declare_lib.nim file
* properly rename api files in library folder
This change is needed so that interoperability with other languages becomes simpler.
Particularly, this simplification is needed from the Python point of view,
where it is tricky to pass a void** as a parameter to an FFI function.
