Checklist

• I have read the OpenWISP Contributing Guidelines.
• I have manually tested the changes proposed in this pull request.
• [] I have written new test cases for new code and/or updated existing tests for changes to existing code.
• [] I have updated the documentation.

Reference to Existing Issue

Closes #276.

Please open a new issue if there isn't an existing issue yet.

Description of Changes

This PR implements the missing WireGuard parsers in WireguardParser inside netjsonconfig/netjsonconfig/backends/wireguard/parser.py.

Changes made:

✅ Implemented parse_text() to parse WireGuard config files into structured dictionaries.
✅ Implemented parse_tar() to handle .tar.gz archives containing multiple WireGuard configurations.
✅ Added helper methods _get_vpns() and _get_config() to extract VPN details.
✅ Updated wireguard.py to integrate the parser.

Example Config Parsed:

[Interface]
Address = 10.0.0.1/24
PrivateKey = abcdefghijklmnopqrstuvwxyz
ListenPort = 51820
DNS = 8.8.8.8

[Peer]
PublicKey = mnopqrstuvwxyzabcdefghij
AllowedIPs = 10.0.0.2/32
Endpoint = 192.168.1.1:51820

Screenshot

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