feat(niri-displays): add rotation, position, and display layout

[psukez]

Plugin

• Id: raycursive/niri-displays
• New plugin
• Update to an existing plugin (version bumped in plugin.toml)

What it does

Adds rotation (transform), position, and a unified Display layout panel to the existing niri-displays plugin.

• Rotation — rotate any connected output (0°/90°/180°/270°) through Niri's transform IPC.
• Position — move an output to any side of another output (top / left / right / bottom) plus a fine-grained pixel offset, through Niri's position IPC.
• Display layout — one unified panel to pick the output, place it with a button cross, fine-tune with a single offset slider, and apply with one button.

Users get full temporary control over how their monitors are arranged and oriented, directly from the Noctalia panel, without editing config.kdl.

External dependencies

• niri — the plugin shells out to niri msg to read output state (niri msg --json outputs, niri msg --json focused-output) and to apply changes (niri msg output <connector> mode/scale/transform/position ...). Listed in plugin.toml under dependencies.

Testing

• Tested on Niri
• Tested on Hyprland
• Tested on Sway
• Tested on another compositor:
• Noctalia version tested against: v5.0.0 (v5.0.0-beta.9-3-g69a90183531d)
• Plugin API level: 9

Screenshots / Videos

The unified Display layout panel:

The panel with the new rotation, position, and display-layout controls:

Checklist

Ready-for-review requirement: Every box in this section must be checked.

• 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:

• 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.

[github-actions]

CC @raycursive