feat(openwrt): add OpenWrt gateway status view and get-status RPC

Backend: new `openwrt.get-status` RPC endpoint SSHes into the saved (or
provided) OpenWrt router and returns system info, TollGate config, and WiFi
AP interfaces via UCI.

Frontend: new OpenWrtGateway.vue view at /dashboard/server/openwrt shows
system hostname, OpenWrt version, uptime, TollGate install/enable state with
pricing and mint URL, and all AP-mode WiFi interfaces. Linked from the Local
Network section of the Server view.

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

core/archipelago/src/api/rpc/dispatcher.rs

@@ -232,6 +232,7 @@ impl RpcHandler {
 
             // OpenWrt / TollGate
             "openwrt.scan" => self.handle_openwrt_scan(params).await,
+            "openwrt.get-status" => self.handle_openwrt_get_status(params).await,
             "openwrt.provision-tollgate" => self.handle_openwrt_provision_tollgate(params).await,
 
             // Ecash wallet