* SubscriptionManager tracks shard and content topic interest
* RecvService emits MessageReceivedEvent on subscribed content topics
* Route MAPI through old Kernel API relay unique-handler infra to avoid code duplication
* Encode current gen-zero network policy: on Core node boot, subscribe to all pubsub topics (all shards)
* Add test_api_subscriptions.nim (basic relay/core testing only)
* Removed any MAPI Edge sub/unsub/receive support code that was there (will add in next PR)
* Hook MessageSeenEvent to Kernel API bus
* Fix MAPI vs Kernel API unique relay handler support
* RecvService delegating topic subs to SubscriptionManager
* RecvService emits MessageReceivedEvent (fully filtered)
* Rename old SubscriptionManager to LegacySubscriptionManager
* introduce createNode
# Conflicts:
# apps/wakunode2/cli_args.nim
* remove confutils dependency on the library
* test: remove websocket in default test config
* update to latest specs
* test: cli_args
* align to spec changes (sovereign, message conf, entrypoints
* accept enr, entree and multiaddr as entry points
* post rebase
* format
* change from "sovereign" to "core"
* add example
* get example to continue running
* nitpicks
* idiomatic constructors
* fix enum naming
* replace procs with consts
* remove messageConfirmation
* use pure enum
* rename example file