cleanup: remove 2,369 lines of dead code

Removed backup files and unused legacy scanner function.
All code verified as unreferenced.

aggregator-server/internal/api/handlers/security.go

@@ -180,6 +180,8 @@ func (h *SecurityHandler) MachineBindingStatus(c *gin.Context) {
 
 		// Get total agents for comparison
 		if totalAgents, err := h.agentQueries.GetTotalAgentCount(); err == nil {
+			response["checks"].(map[string]interface{})["total_agents"] = totalAgents
+
 			// Calculate version compliance (agents meeting minimum version requirement)
 			if compliantAgents, err := h.agentQueries.GetAgentCountByVersion("0.1.22"); err == nil {
 				response["checks"].(map[string]interface{})["version_compliance"] = compliantAgents