Add hide-when-unused toggle for bar widget in screen-toolkit

[Ahmed5Emad]

Plugin

• Id: alexander/screen-toolkit

• New plugin
• Update to an existing plugin (version bumped in plugin.toml)

What it does

Adds Hide when unused toggle to the bar widget (fixes #444). When enabled (hide-when-unused=true), the widget is hidden via barWidget.setVisible(false) unless recording==true; it appears only while a recording is active. Hotkey / IPC noctalia msg panel-toggle alexander/screen-toolkit:panel and the control-center shortcut still work while hidden. Default false preserves current behavior.

closes issue #444

External dependencies

Testing

• Tested on Niri
• Tested on Hyprland
• Tested on Sway
• Tested on another compositor:
• Noctalia version tested against: 5.0.0 beta 8
• Plugin API level: 13

Screenshots / Videos

Checklist

Ready-for-review requirement: Every box in this section must be checked. If any statement is not true, keep the
pull request as Draft. An explanation does not replace a required check.

• The directory name matches the part of id after the / in plugin.toml exactly.
• It ships plugin.toml, README.md, thumbnail.webp, and translations/en.json.
• README.md follows the
  README template, documents
  every entry id and dependency, and includes exact panel IPC commands and launcher prefixes where applicable.
• I created thumbnail.webp with the thumbnail generator.
• version follows semver and is bumped in this PR; plugin_api is the oldest API level this plugin requires.
• Every non-English translation in this PR uses a locale supported by Noctalia core, and I can read, write, and
  understand that language well enough to review and maintain it (no unreviewed machine/LLM translations).
• I did not edit catalog.toml; CI generates it.
• This PR touches exactly one plugin directory.

Code review attestation

Plugins run as trusted, unsandboxed Luau in the user's session. Confirm:
Ready-for-review requirement: Every attestation below must be checked.

• The code is readable and not obfuscated, minified, or generated.
• It does not download and execute remote code.
• Every network call, filesystem write, and spawned process is something the description above accounts for.
• I have the right to publish this code under the license declared in plugin.toml.