feat/use operation mode availability for emergency handler

[asana17]

Description

Changed emergency handler to use the operation mode availability, and added pull over operator interface.

Related links

Tests performed

Tested with planning simulator and mock nodes that publish operation mode availability and deal with mrm pull over operation.
(Mock nodes are available in safety_island repository: https://github.com/tier4/safety_island/tree/feat/use-system-diagnostic-graph/src .)

Notes for reviewers

Interface changes

Effects on system behavior

Pre-review checklist for the PR author

The PR author must check the checkboxes below when creating the PR.

• I've confirmed the contribution guidelines.
• The PR follows the pull request guidelines.

In-review checklist for the PR reviewers

The PR reviewers must check the checkboxes below before approval.

• The PR follows the pull request guidelines.
• The PR has been properly tested.
• The PR has been reviewed by the code owners.

Post-review checklist for the PR author

The PR author must check the checkboxes below before merging.

• There are no open discussions or they are tracked via tickets.
• The PR is ready for merge.

After all checkboxes are checked, anyone who has write access can merge the PR.