Function infer_config 

pub fn infer_config(source_dir: &Path) -> Result<InferredConfig, CodegenError>

Walk source_dir and infer a plumb_core::Config from the design-token sources it finds.

The walker is bounded by MAX_WALK_DEPTH and skips node_modules, target, dist, build, .next, out, and any dotfile directory.

Errors

• CodegenError::NotFound if source_dir does not exist.
• CodegenError::NotADirectory if source_dir is not a directory.
• CodegenError::Io if a directory entry cannot be read.
• CodegenError::Source if a discovered token source fails to parse. Parse errors carry the source span via plumb_config::ConfigError.