exgfr/Pike

AI Summary: Implement comprehensive error handling for all store operations within the Pike Elixir library. This involves detecting errors during key retrieval, insertion, deletion, and updates, and propagating these errors appropriately to the `on_auth_failure` handler, using the existing `:store_error` reason. The goal is to prevent silent failures and provide informative error responses to API clients.

AI Summary: Implement API key format validation in the Pike Elixir library to prevent malformed keys from being processed. This involves adding a validation step within the authentication process, likely using a regular expression to define acceptable key formats, and returning the `:invalid_format` error if the validation fails. The implementation should be backward compatible and should not break existing functionality.

AI Summary: Implement API key expiration functionality in the Pike Elixir library. This involves adding fields to store expiration dates (e.g., a `expires_at` timestamp), modifying the `Pike.Store` interface to handle expiration checks, updating the `Pike.AuthorizationPlug` to validate against the expiration date, and potentially adding helper functions for key creation/update to manage expiration dates. The `:expired` failure reason already exists, so the implementation needs to trigger this reason when appropriate.