feat(ansible): add OpenWrt dlink AP configuration

Add community.openwrt collection, dlink host to inventory,
openwrt role with system/network/firewall tasks, and two
playbooks: dlink-init.yml for one-time bootstrap from factory
IP, and openwrt.yml for ongoing idempotent configuration.

Network: MGMT untagged + LAN (vlan2) tagged on WAN port trunk
to MikroTik ether3. Firewall zones replace factory WAN/LAN
with mgmt (input ACCEPT) and lan (forward ACCEPT, AP mode).

ansible/roles/openwrt/tasks/system.yml

@@ -0,0 +1,30 @@
+---
+- name: Set hostname
+  community.openwrt.uci:
+    command: set
+    key: system.@system[0].hostname
+    value: "{{ openwrt_hostname }}"
+
+- name: Set timezone
+  community.openwrt.uci:
+    command: set
+    key: system.@system[0].timezone
+    value: "{{ openwrt_timezone }}"
+
+- name: Configure NTP servers
+  community.openwrt.uci:
+    command: set
+    key: system.ntp.server
+    value: "{{ openwrt_ntp_servers }}"
+
+- name: Commit system config
+  community.openwrt.uci:
+    command: commit
+    key: system
+
+- name: Set SSH authorized keys
+  community.openwrt.uci:
+    command: set
+    key: "dropbear.@dropbear[0].authorized_keys"
+    value: "{{ openwrt_ssh_authorized_keys | join('\n') }}"
+  when: openwrt_ssh_authorized_keys | length > 0