refactor: simplify gpiod sensor trigger implementation

[bgilby59]

PR Type

• Improvement

Description

This PR refactors sensor_trigger gpiod implementation to remove unnecessary code, correct misleading comments, and follow gpiod naming conventions for gpio manipulation.

Review Procedure

• Build edge-auto-jetson
• Run edge-auto-jetson with perception:=false
• Check trigger_time and image_raw ROS2 topics with ros2 topic hz <topic_name>

Pre-Review Checklist for the PR Author

PR Author should check the checkboxes below when creating the PR.

• [x] Assign PR to reviewer

Checklist for the PR Reviewer

Reviewers should check the checkboxes below before approval.

• [x] Commits are properly organized and messages are according to the guideline
• [x] (Optional) Unit tests have been written for new behavior
• [x] PR title describes the changes

Post-Review Checklist for the PR Author

PR Author should check the checkboxes below before merging.

• [ ] All open points are addressed and tracked via issues or tickets

CI Checks

• Build and test for PR: Required to pass before the merge.