Function get_storage_type 

pub fn get_storage_type() -> &'static str

Returns the active storage backend type.

Useful for debugging and diagnostics.

Returns

• "server" — HTTP headers (server-side)
• "keychain" — System keyring (desktop/mobile)
• "file" — Encrypted file fallback (iOS Simulator, debug only)
• "browser" — document.cookie (WASM)
• "stub" — No-op implementation
• "uninitialized" — init not yet called