Add nftables WAN open ports as sub-services

Display open external ports from nftables firewall rules as sub-services
grouped by protocol. Only shows WAN incoming ports by filtering input chain
rules and excluding private network sources.

- Parse nftables ruleset for accept rules with dport in input chain
- Filter out internal network traffic (192.168.x, 10.x, 172.16.x, loopback)
- Extract single ports and port sets from rules
- Group and display as "TCP: 22, 80, 443" and "UDP: 53, 123"
- Update version to v0.1.247

Cargo.lock

@@ -279,7 +279,7 @@ checksum = "a1d728cc89cf3aee9ff92b05e62b19ee65a02b5702cff7d5a377e32c6ae29d8d"
 
 [[package]]
 name = "cm-dashboard"
-version = "0.1.245"
+version = "0.1.247"
 dependencies = [
  "anyhow",
  "chrono",
@@ -301,7 +301,7 @@ dependencies = [
 
 [[package]]
 name = "cm-dashboard-agent"
-version = "0.1.245"
+version = "0.1.247"
 dependencies = [
  "anyhow",
  "async-trait",
@@ -325,7 +325,7 @@ dependencies = [
 
 [[package]]
 name = "cm-dashboard-shared"
-version = "0.1.245"
+version = "0.1.247"
 dependencies = [
  "chrono",
  "serde",