feat: add Timezone Hub plugin

[Ahmedhossamdev]

Plugin

• Id: ahmedhossamdev/timezone-hub
• New plugin
• Update to an existing plugin (version bumped in plugin.toml)

What it does

Timezone Hub adds a multi-timezone clock to the Noctalia bar and a comparison
panel for dates, working hours, relative time differences, and optional local
sunrise and sunset calculations. Users can show up to three timezones in the
bar and can change the device timezone from the panel.

External dependencies

• timedatectl — detects the device timezone, lists IANA timezones, and applies
  device-wide timezone changes.
• pkexec — opens the polkit authorization prompt required to change the
  device timezone.
• /usr/share/zoneinfo/zone1970.tab or /usr/share/zoneinfo/zone.tab — optional
  system timezone coordinate data used for local sunrise and sunset
  calculations.

The plugin makes no network calls.

Testing

Tested the bar widget with one, two, and three selected timezones. Tested the
panel by adding, removing, reordering, and selecting timezones for the bar;
changing the device timezone; navigating the hour comparison; toggling date,
relative-time, working-hour, and sunrise/sunset settings; and restarting the
plugin to confirm saved state is restored.

• Tested on Niri
• Tested on Hyprland
• Tested on Sway
• Tested on another compositor:
• Noctalia version tested against: noctalia v5.0.0 (5.0.0_beta.10-1-dirty)
• Plugin API level: 24

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.
• thumbnail.webp is present and relevant; for a new plugin I created it with the thumbnail generator, and for an update I regenerated it with the generator if the visual identity or user-facing appearance changed.
• 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.