network applet: fix WireGuard connection state handling

[wocisjr]

Three separate issues in the WireGuard part of the network applet:

• NMDeviceWIREGUARD kept a single _activeConnection, so when more than one tunnel was up, _syncActiveConnections() overwrote it once per active connection and only the last one seen was shown as connected. It now keeps a list of active connections, mirroring what NMDeviceVPN already does, so every tunnel that is up gets its dot, and clicking a row toggles that specific tunnel instead of only ever activating it.

• _connectionRemoved() called this._connections.splice(pos) without a delete count, which drops every element from pos to the end of the array rather than the single removed connection. Removing one profile could therefore silently discard unrelated ones from the applet's bookkeeping, leaving menu rows without their label or toggle state until Cinnamon was restarted.

• _updateIcon() runs entirely inside a try/catch, so anything thrown in it leaves the icon and tooltip frozen at their previous values. Two throws lived there: reading _switch.state off this._devices.wireguard.item without checking that the switch exists, and dereferencing mc._section in the VPN loop when there is no main connection at all. Both are now guarded, and the VPN and WireGuard cases share one code path.

The tooltip now also names every active tunnel rather than just the first.

Tested against NetworkManager 1.46.0 on Cinnamon 6.6.9 with three concurrent WireGuard tunnels, including removing both a running and a stopped profile.

[github-actions]

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Found 2 potential issue(s):

⚠️ WARNING

⚠️ lang_bind

files/usr/share/cinnamon/applets/network@cinnamon.org/applet.js:1157

obj.item.connect('activate', Lang.bind(this, function() {

Lang.bind() is deprecated. Use arrow functions (() => {}) or Function.prototype.bind() instead.

files/usr/share/cinnamon/applets/network@cinnamon.org/applet.js:1965

this._devices.wireguard.device.connect('active-connections-changed', Lang.bind(this, function() {

Lang.bind() is deprecated. Use arrow functions (() => {}) or Function.prototype.bind() instead.

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Automated pattern check.