feat(plugins): add update all CLI flag and settings updates dialog

[hthienloc]

Description

Adds options to check and perform bulk plugin updates via the dms CLI and front-end settings.

What:

1. CLI Commands:
   • Added --all / -a flag to dms plugins update to update all plugins sequentially.
   • Added --check flag to dms plugins update to fetch and list outdated plugins without executing changes.
   • Updated dms plugins list to display (update available) next to any outdated plugins.
   • Skip system-wide plugins gracefully during bulk updates with a skip warning.
2. Settings UI Dialog:
   • Registered PluginUpdatesDialog to list plugins with pending updates, styled with primary action buttons (Update, Update All) and neutral secondary controls (Diff, Cancel).
   • Implemented precise Git commit comparison URLs (github.com/user/repo/compare/local_head...remote_head) under the "Diff" button.

Why:

• Enables package managers (e.g. topgrade) and automation tools to check and update plugins cleanly, and improves front-end UX by exposing commit comparison diffs before updating.

How tested:

1. Compiled the Go daemon with make build.
2. Verified dms plugins list highlights update availabilities.
3. Verified dms plugins update --check --all returns only outdated plugin lists and exits correctly.
4. Validated QML dialog interaction, diff generation, and update operations.

Type of change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that changes existing behavior)
• Refactor / internal cleanup
• Documentation
• Other

Related issues

Closes #2175

Screenshots / video

recording_20260622_121221.mp4

Checklist

• My code follows the conventions in CONTRIBUTING.md
• I have tested my changes locally
• New user-facing strings are wrapped in I18n.tr() with translator context, reusing existing terms where possible
• Go changes: ran make fmt, added/updated tests, make test passes, and go mod tidy is clean
• QML changes: ran make lint-qml with no new warnings
• I have opened a corresponding pull request in dlx-docs to document any new behaviors: https://github.com/AvengeMedia/DankLinux-Docs