factor(route): make proxmox validation non-critical

Proxmox validation errors are now logged and ignored rather than
causing route validation to fail, allowing routes to function even
when proxmox integration encounters issues.

- Extract proxmox validation into dedicated validateProxmox() method
- Log warnings/errors instead of returning validation errors
- Add warning when proxmox config exists but no node/resource found

internal/proxmox/client.go

@@ -14,7 +14,6 @@ import (
 	"sync"
 
 	"github.com/luthermonson/go-proxmox"
-	"github.com/rs/zerolog/log"
 	"golang.org/x/sync/errgroup"
 )
 
@@ -120,7 +119,6 @@ func (c *Client) UpdateResources(ctx context.Context) error {
 		c.resources[resource.ID] = vmResources[i]
 	}
 	c.resourcesMu.Unlock()
-	log.Debug().Str("cluster", c.Cluster.Name).Msgf("[proxmox] updated %d resources", len(c.resources))
 	return nil
 }