Add live reload support for Noctalia/Quickshell template updates #176
Description
Problem
Dumber can be themed via generated config files, but it does not automatically react when Noctalia (Quickshell) regenerates templates after a color scheme change.
Today, users have to restart Dumber or manually reload to see updated colors.
Proposal
Add a lightweight config/theme watcher so Dumber can hot-apply appearance updates when theme/template files change on disk.
Suggested scope:
- Watch ~/.config/dumber/config.toml (and optionally an include/theme file if added later).
- On file change, reload appearance settings at runtime (at least palette plus accent/border values).
- Avoid full app restart; apply updates to existing UI surfaces where possible.
- Debounce rapid writes to avoid duplicate reloads during template generation.
Why
This would make Dumber integrate cleanly with Noctalia template workflows (Matugen), where external app themes regenerate automatically whenever the user changes color scheme.
Acceptance Criteria
- Changing Noctalia color scheme updates Dumber appearance without restart.
- No noticeable flicker or repeated reload loops.
- Invalid config changes fail safely (keep previous valid theme and log warning).