Basic Plaid Integration

[zachgoll]

WIP

Done

• [x] Plaid Link flow
• [x] Plaid accounts and balance syncing
• [x] Plaid webhook setup + JWT header verification
• [x] Account management view
• [x] Old "institution" view replaced with "Plaid Item"

Todo

• [x] Transaction syncing
• [ ] Investment trade syncing
• [ ] Liability information (credit cards, loans) syncing