feat(netbox): add module-based tool filtering for token optimization

Reduces NetBox MCP context token consumption from ~19,810 tokens (182 tools)
to ~4,500 tokens (~43 tools) by enabling environment-variable-driven module
filtering.

Key changes:
- Add NETBOX_ENABLED_MODULES env var to config.py
- Filter tool registration based on enabled modules in server.py
- Conditional tool class instantiation for memory efficiency
- Routing guard with clear error messages for disabled modules
- Startup logging shows enabled modules and tool count

Also fixes documentation referencing incorrect tool names:
- virtualization_* → virt_* in cmdb-assistant docs
- wireless_* → wlan_* in README
- circuits_list_circuit_terminations → circ_list_terminations

Recommended config for cmdb-assistant users:
NETBOX_ENABLED_MODULES=dcim,ipam,virtualization,extras

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

plugins/cmdb-assistant/claude-md-integration.md

@@ -32,9 +32,9 @@ The following NetBox MCP tools are available for infrastructure management:
 - `ipam_list_available_ips`, `ipam_create_available_ip` - IP allocation
 
 **Virtualization:**
-- `virtualization_list_virtual_machines`, `virtualization_create_virtual_machine` - VM management
-- `virtualization_list_clusters`, `virtualization_create_cluster` - Cluster management
-- `virtualization_list_vm_interfaces` - VM interface management
+- `virt_list_vms`, `virt_create_vm`, `virt_update_vm`, `virt_delete_vm` - VM management
+- `virt_list_clusters`, `virt_create_cluster`, `virt_update_cluster`, `virt_delete_cluster` - Cluster management
+- `virt_list_vm_ifaces`, `virt_create_vm_iface` - VM interface management
 
 **Circuits:**
 - `circuits_list_circuits`, `circuits_create_circuit` - Circuit management