Enhance HMAC timestamp validation: improve parsing logic and add test…

[GrantBirki]

…s for ISO 8601 UTC format

[Copilot]

Pull Request Overview

This PR enhances timestamp validation for HMAC authentication by unifying parsing to epoch seconds, tightening input checks, and adding an acceptance test for Ruby’s default ISO 8601 format.

• Added an acceptance test covering Time.now.utc.iso8601 timestamps
• Refactored parse_timestamp to reject control chars/whitespace and return integer seconds
• Updated ISO 8601 regex and parsing to use Time.parse, with warning logs for invalid inputs

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
spec/acceptance/acceptance_tests.rb	Added acceptance test for ISO 8601 timestamps using Ruby’s iso8601 method
lib/hooks/plugins/auth/hmac.rb	Refactored timestamp parsing: control-character checks, unified return type, regex adjustment

Comments suppressed due to low confidence (1)

spec/unit/hooks/plugins/auth/hmac_spec.rb:1

• There are no unit tests covering parse_timestamp, parse_iso8601_timestamp, and parse_unix_timestamp edge cases (e.g., invalid formats, control characters, whitespace); consider adding tests to verify each path.

// new tests for parse_timestamp