pantallas@jorge: add applet to control brightness and colour temperature

[jorgesenosiain]

New applet: Pantalla (pantallas@jorge). Controls screen brightness and colour temperature from the Cinnamon panel, with customizable modes (Day, Night…) and automatic day/night switching. Software-based via xrandr (works on any monitor, multi-monitor; X11). Requirements: Cinnamon on X11 + xrandr (preinstalled), no other dependencies. Author: @jorgesenosiain. License: GPL-3.0.

[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.

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Found 3 potential issue(s):

⚠️ WARNING

⚠️ sync_spawn_command_line

pantallas@jorge/files/pantallas@jorge/applet.js:309

let [ok, out] = GLib.spawn_command_line_sync("xrandr --query");

Synchronous process spawning blocks the main loop.
Use GLib.spawn_command_line_async() or Gio.Subprocess instead.

ℹ️ INFO

ℹ️ shell_string_spawn

pantallas@jorge/files/pantallas@jorge/applet.js:309

let [ok, out] = GLib.spawn_command_line_sync("xrandr --query");

Prefer argument vector spawn functions over shell command strings.
This is especially important when arguments include untrusted input (user data,
filenames, settings values, etc.) as shell strings are vulnerable to injection.
Static command strings are generally fine, but argv is always safer.
Use Util.spawn(["cmd", "arg1", "arg2"]) or Util.trySpawn() instead.

pantallas@jorge/files/pantallas@jorge/applet.js:342

Util.spawnCommandLine(parts.join(" "));

Prefer argument vector spawn functions over shell command strings.
This is especially important when arguments include untrusted input (user data,
filenames, settings values, etc.) as shell strings are vulnerable to injection.
Static command strings are generally fine, but argv is always safer.
Use Util.spawn(["cmd", "arg1", "arg2"]) or Util.trySpawn() instead.

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Automated pattern check.