fix: separate switch inventory to prevent accidental targeting

Move switches.yml to inventory-switches/ so ansible.cfg's
`inventory = inventory/` only loads biscayne. Switch playbooks
must pass `-i inventory-switches/` explicitly.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

inventory/switches.yml

@@ -1,23 +0,0 @@
-all:
-  children:
-    switches:
-      vars:
-        ansible_connection: ansible.netcommon.network_cli
-        ansible_network_os: arista.eos.eos
-        ansible_user: install
-        ansible_become: true
-        ansible_become_method: enable
-      hosts:
-        was-sw01:
-          ansible_host: 137.239.200.198
-          # Et1/1: 64.92.84.81 (Ashburn uplink)
-          # Et4/1: 172.16.1.188 (backbone to mia-sw01)
-          # Loopback100: 137.239.194.64/32
-          backbone_ip: 172.16.1.188
-          backbone_peer: 172.16.1.189
-          uplink_gateway: 64.92.84.80
-        mia-sw01:
-          ansible_host: 209.42.167.133
-          # Et4/1: 172.16.1.189 (backbone to was-sw01)
-          backbone_ip: 172.16.1.189
-          backbone_peer: 172.16.1.188