[OpAMP] fleet-server should decode all agent capabilities

[michel-laterman]

fleet-server currently only decodes a subset of agent capabilities:

fleet-server/internal/pkg/api/handleOpAMP.go

Lines 514 to 531 in 52f9cbe

	// decodeCapabilities converts capability bitmask to human-readable strings
	func decodeCapabilities(caps uint64) []string {
	var result []string
	capMap := map[uint64]string{
	uint64(protobufs.AgentCapabilities_AgentCapabilities_ReportsStatus): "ReportsStatus",
	uint64(protobufs.AgentCapabilities_AgentCapabilities_AcceptsRemoteConfig): "AcceptsRemoteConfig",
	uint64(protobufs.AgentCapabilities_AgentCapabilities_ReportsEffectiveConfig): "ReportsEffectiveConfig",
	uint64(protobufs.AgentCapabilities_AgentCapabilities_ReportsHealth): "ReportsHealth",
	uint64(protobufs.AgentCapabilities_AgentCapabilities_ReportsAvailableComponents): "ReportsAvailableComponents",
	uint64(protobufs.AgentCapabilities_AgentCapabilities_AcceptsRestartCommand): "AcceptsRestartCommand",
	}
	for mask, name := range capMap {
	if caps&mask != 0 {
	result = append(result, name)
	}
	}
	return result
	}

This should be changed to decode all possible settings - ideally the upstream AgentCapabilities_name could be used