network applet: optional VPN list cap with overflow submenu (#13562)

[araujorm]

Fixes #13562.

NMDeviceVPN._createSection lists every configured VPN inline regardless of count, unlike the wired, wireless, mobile broadband and WireGuard sections, which cap at NUM_VISIBLE_NETWORKS (5). With many VPN connections the menu exceeds the monitor height and the items below (Network Settings, Network Connections) become unreachable.

The patch adds a per-instance cap to NMDeviceVPN, exposed through two new settings:

• "Limit VPN list" (switch, default off): gates the behaviour.
• "Visible VPN connections before "More"" (spinbutton, default 5, range 1-50, shown via dependency only when the switch is on): cap value.

When the switch is off the cap is Infinity, so the popup looks exactly like an unpatched Cinnamon 6.6.x. When on, items beyond the cap move into a "More" submenu, matching the existing behaviour of the other sections.

Tested on Fedora 44 (cinnamon-6.6.7-5.fc44) with 27 configured VPN connections.

[github-actions]

Best-practices scanner

This is a regex-based check for API usage that can pose security, performance or
maintainability issues, or that may already be provided by Cinnamon. Most findings
are advisory and do not automatically disqualify a pull request.

This check is not perfect and will not replace a normal review.

---

Found 2 potential issue(s):

⚠️ WARNING

⚠️ lang_bind

files/usr/share/cinnamon/applets/network@cinnamon.org/applet.js:1839

this.settings.bind("cap-vpn-list", "_capVpnList", Lang.bind(this, this._onVpnCapChanged));

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

files/usr/share/cinnamon/applets/network@cinnamon.org/applet.js:1840

this.settings.bind("num-visible-vpns", "_numVisibleVpns", Lang.bind(this, this._onVpnCapChanged));

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

---

Automated pattern check.

[araujorm]

Best-practices scanner

This is a regex-based check for API usage that can pose security, performance or maintainability issues, or that may already be provided by Cinnamon. Most findings are advisory and do not automatically disqualify a pull request.

This check is not perfect and will not replace a normal review.

Found 2 potential issue(s):

⚠️ WARNING

⚠️ lang_bind

files/usr/share/cinnamon/applets/network@cinnamon.org/applet.js:1839

this.settings.bind("cap-vpn-list", "_capVpnList", Lang.bind(this, this._onVpnCapChanged));

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

files/usr/share/cinnamon/applets/network@cinnamon.org/applet.js:1840

this.settings.bind("num-visible-vpns", "_numVisibleVpns", Lang.bind(this, this._onVpnCapChanged));

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

Automated pattern check.

Fixed in latest push.