Function generate_static_cache 

pub fn generate_static_cache(locales_dir_path: &str)

Generates the static cache code for fluent-zero.

This function reads Fluent (.ftl) files from the specified directory, parses them, and generates a Rust file (static_cache.rs) in the OUT_DIR.

Process

1. Scans locales_dir_path for language subdirectories (e.g., en-US).
2. Parses every .ftl file found.
3. Identifies Static messages (no variables, standard text) vs Dynamic messages.
4. Generates:
   • CACHE: A Perfect Hash Map (PHF) mapping keys to CacheEntry::Static(&str) or CacheEntry::Dynamic.
   • LOCALES: A Map of Lazy-loaded ConcurrentFluentBundles for fallback/dynamic resolution.

Arguments

• locales_dir_path - Relative path to the folder containing locale subdirectories.