fix(pkg/p2p): purge gater blocklist on restart by using in-memory datastore

Stale blocklist entries accumulated in the Badger datastore were causing
the edennet-2 incident (#3267): fullnodes rejected every
binary builder peer, header sync never initialized, and nodes fell back
to DA-only sync.

Fixes the root cause by giving BasicConnectionGater a fresh in-memory
datastore on every startup instead of the persistent one. The blocklist
is always empty at boot; config-driven blocks (conf.BlockedPeers) are
still re-applied each run via setupBlockedPeers. This is ADR-023 Option A.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: auricom

pkg/p2p/client.go

@@ -82,7 +82,11 @@ func NewClient(
 	metrics *Metrics,
 ) (*Client, error) {
 
-	gater, err := conngater.NewBasicConnectionGater(ds)
+	// Use a fresh in-memory datastore so the gater blocklist is always clean on
+	// restart. Persistent config blocks (conf.BlockedPeers) are re-applied each
+	// time startWithHost runs. Dynamic runtime bans are intentionally ephemeral.
+	// The ds parameter is reserved for the future TTL gater (ADR-023 Option C).
+	gater, err := conngater.NewBasicConnectionGater(datastore.NewMapDatastore())
 	if err != nil {
 		return nil, fmt.Errorf("failed to create connection gater: %w", err)
 	}