[10.4.x]: Live: Add ha_prefix (#93759) (#93927)

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Co-authored-by: Todd Treece <360020+toddtreece@users.noreply.github.com>

pkg/setting/setting.go

@@ -428,6 +428,8 @@ type Cfg struct {
 	// LiveHAEngine is a type of engine to use to achieve HA with Grafana Live.
 	// Zero value means in-memory single node setup.
 	LiveHAEngine string
+	// LiveHAPRefix is a prefix for HA engine keys.
+	LiveHAPrefix string
 	// LiveHAEngineAddress is a connection address for Live HA engine.
 	LiveHAEngineAddress  string
 	LiveHAEnginePassword string
@@ -1984,6 +1986,7 @@ func (cfg *Cfg) readLiveSettings(iniFile *ini.File) error {
 	default:
 		return fmt.Errorf("unsupported live HA engine type: %s", cfg.LiveHAEngine)
 	}
+	cfg.LiveHAPrefix = section.Key("ha_prefix").MustString("")
 	cfg.LiveHAEngineAddress = section.Key("ha_engine_address").MustString("127.0.0.1:6379")
 	cfg.LiveHAEnginePassword = section.Key("ha_engine_password").MustString("")