Function resolve_base_url

pub fn resolve_base_url(input: &str) -> RovenueResult<String>

Resolve a caller-supplied base URL:

• blank (after trim) → DEFAULT_BASE_URL
• https://… accepted
• http://… accepted ONLY for localhost / 127.0.0.1 / [::1] and the Android emulator’s host alias 10.0.2.2 (local dev)
• anything else → RovenueError::InvalidArgument()