fix(ui): better autoupdate plugin ui

[AdityaKr015]

Summary

Just a better UI PR. Makes All sources/Official Only/None into All/Official/None with matching width of dropdown

Motivation

On some scaling Official Only gets truncate it makes UI bad, so this is a fix for it.

Type of Change

• Bug fix
• New feature
• Breaking change
• Refactoring
• Build / packaging

Testing

• just format, just test, just lint, python3 tools/i18n-check.py all clean

Manual Coverage

• Tested on Niri
• Tested on Hyprland
• Tested on Sway
• Tested on another compositor: Umbriel
• Tested with different bar positions and density settings
• Tested at different interface scaling values
• Tested with multiple monitors

Screenshots / Videos

Before:-

After:-

This is with width 100.0F, i forgot to click with 110.0F, which looks even better, same width selection box with dropdown

Checklist

• This PR is ready for review.
• I read and followed the relevant guidance in CONTRIBUTING.md.
• I ran just format with clang-format v22+ installed.
• I ran the relevant build or test commands.
• I self-reviewed the changes.
• I checked for new warnings or errors.
• [] I will update end-user documentation after merge, or this PR does not change user-facing configuration or behavior.
• I added or updated assets/translations/en.json, or this PR adds no new user-facing strings.
• I did not edit non-English translation files unless this PR is explicitly for translation tooling, an import/export sync, or a maintainer-requested locale change.
• I used the existing canonical names for config keys, IPC names, paths, and identifiers.