Library Maintenance: Fix typescript-eslint errors

Fixing #5532 required the turning off of several typescript rules, listed below.

Turn them back on and fix the errors they throw. Some will throw a significant amount of errors (on the order of more than 1,000) while others will throw dozens of errors.

```
@typescript-eslint/ban-types
@typescript-eslint/no-floating-promises
@typescript-eslint/no-misused-promises
@typescript-eslint/no-unsafe-argument
@typescript-eslint/no-unsafe-assignment
@typescript-eslint/no-unsafe-call
@typescript-eslint/no-unsafe-member-access
@typescript-eslint/no-unsafe-return
@typescript-eslint/prefer-as-const
@typescript-eslint/restrict-plus-operands
@typescript-eslint/restrict-template-expressions
```