* get most recent tasks based on last_state_change instead of task_model.id
* added api to get task instances of a task
* some changes to support displaying task instances
* forgot to commit the controller
* updated frontend to display info for other instances of a task w/ burnettk
* some formatting to the selected task instance w/ burnettk
* do not get task instances when selecting different instance w/ burnettk
* added tests for task-instances w/ burnettk
* some ui tweaks for task instance view w/ burnettk
* updates based on coderabbit
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Co-authored-by: jasquat <jasquat@users.noreply.github.com>