pub fn discover_themes(
layers: &[DiscoveryLayer],
) -> Result<Vec<ThemeResource>, ThemeDiscoveryError>Expand description
Discover themes across multiple layers with precedence-based deduplication.
Each layer’s scan directory is enumerated for subdirectories containing
theme.toml files. When multiple layers produce themes with the same
name, the one with the highest precedence value is kept. Duplicate names
within the same precedence layer are reported as an error.
Returns the deduplicated list of discovered theme resources, sorted by name. Missing scan directories are silently skipped.