Refactor objects to use Pydantic models

[jbriones1]

Currently, a lot of the tables.py files hold classes that have their own patching and serialization functions (see OfficerTerm in src/officers/tables.py. We should just let Pydantic's built in features handle that since it can handle serialization, patching, and validation. The data flow would look something like:

1. GET request -> server
2. Fetch the entry/entries from the database as SQL table entries <Table>DB
3. SQL Table Model -> (process data) -> Pydantic Model <Model>.model_validate(<TableDB>)
4. Use Pydantic's serialize <Model>.model_dump_json() -> Send reponse

For requests that take in data, like POST/PATCH/PUT:

1. POST/PATCH/PUT -> server
2. [if PATCH/PUT] fetch entry(ies) from database -> put in Pydantic model, otherwise create a new Pydantic model
3. update the edited/new entry with the data, using Pydantic's function to do it
4. Use Pydantic's validation method to ensure the data is good
5. Convert to a SQL Table Model and send it to the database

To do this we'd need to:

• Create a valid Pydantic model that covers all of the CRUD operations with proper validation fields that match the SQL table models (sort of done)
• Remove the validation, serialization, and patching functions from each of the SQL table models
• Update all the URL endpoints with the Pydantic models (sort of done)