Improve expansion run page performance

[AaronPlave]

Dynamically fetch expansion run details on run row click in the top table instead of fetching all of the nested data for all expansion runs up front. This should significantly improve page load times in scenarios like #1811. Closes #1811.

Verification

1. Use the DB seed scripts to insert expansion rules in the DB.
2. Run PlanDev and create a test model with some activities
3. Run expansion rules on your plan multiple times to generate some expansion runs
4. Go to the Expansion page in the menu
5. Go to the Runs tab in the top right
6. Open your network tab and refresh
7. Look at network requests for the expansion run and verify that only one run is being loaded at a time

OR run this branch on deployment with a large number of expansion runs already in the database, and verify that the Expansion Runs page no longer loads slowly.