Allow Plan Bounds to be Changed

[Mythicaeda]

• Tickets addressed: Closes Change plan start and end bounds #1616
• Review: By commit
• Merge strategy: Merge (no squash)

Description

Adds a trigger to the Plan table to cascade updates to plan bounds to dependent tables
- specifically: activity_directive, simulation_dataset, and plan_dataset
- simulation bounds are NOT automatically updated by this trigger
- a snapshot is automatically taken when this trigger fires

Adds columns to the Plan Snapshots table to track plan boundaries at the time of snapshot creation

• updates the Create and Restore Snapshot functions to restore plan boundaries

Updates the "Update Plan Revision when Activity Directive is Updated" trigger to not fire if another trigger updates the activity_directive table

• Manually verified that the only trigger-originating update to Activity Directive is from the new trigger on Plan. All other updates to the Activity Directive table are either from function calls (ie commit_merge, delete_activity_by_pk_reanchor_subtree) or via user GQL requests
• If we want to avoid this update, we could pull the trigger function into a manually-called Hasura function, similar to how we handled model migration and keep the restriction on updating the DB column

Verification

TODO

Documentation

Future work