Actual Admin View

The admin CLI worked fine for Joel and myself, however for whoever is evals next they're going to want a admin UI

The UI should provide:
- Start a new package season
- Sync Freshmen
- Sync Upperclassmen
- Remove Signatures

... Basically all commands the current CLI gives you

Start by inventorying the current admin CLI and its commands for starting a package season, syncing freshmen and upperclassmen, and removing signatures. Then identify the existing Flask UI entry points and determine how those operations should be exposed; done means the UI provides all commands currently available in the CLI.

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