#3606 feat: Allow config and functions access in stream maps `__alias__` expressions Pull request opened by KaruturiS This PR refactors _eval_stream from a static method to an instance method, allowing stream aliases to access self.map_config and functions. This enables dynamic aliasing based on user configuration. Summary by Sourcery Allow stream alias expressions to be evaluated with mapper instance context, including configuration and helper functions. New Features: • Enable stream alias expressions to access mapper configuration via a config variable. • Expose common helper functions (md5, sha256, datetime, bool, json) to stream alias expressions for dynamic alias generation. Tests: • Add parameterized tests verifying alias expressions can use configuration values and md5 hashing for stream name aliases. meltano/sdk