[BugFix] Make User Preferences -> Defaults Work With Any Parameter

[deeleeramone]

1. Why?:

   • The "defaults" section of the user_settings.json was not able to cope with anything other than "provider".
   • The app fails to import if the defaults configuration is incorrect.

2. What?:

   • Fixes the Defaults class so that validation errors don't happen when supplying other parameters.
     • Issue here was being unnecessarily, overly, specific with type hints.
   • Applies any defaults in the Container/Command classes if they are not supplied at runtime.
   • In the API: Default params will only work where the API has a default of None for the parameter.
   • Resolves [Bug] Provider fallback mechanism fails when endpoint is serviced by provider with API key but endpoint does not require API key. #6686 via bypassing Provider Fallback if there is only one provider. Not a full solution, but will cover most scenarios in the custom router/provider world.

3. Impact:

   • Improved configurability.
   • The API only partially supports this behavior because all mandatory fields need to be supplied to the URL.

4. Testing Done:

   • Ran integration tests and have not found unexpected behavior.

User Settings:

{
  "defaults": {
    "commands": {
      "/equity/price/historical": {
        "provider": "yfinance",
        "chart": true,
        "chart_params": {
          "heikin_ashi": true,
          "indicators": {
            "sma": {
              "length": [21, 50]
            },
            "ema": {
              "length": 150
            }
          }
        }
      }
    }
  }
}

Before:

from openbb import obb

ValidationError: 2 validation errors for UserSettings
defaults.commands.`equity.price.historical`.chart
  Input should be a valid list [type=list_type, input_value=True, input_type=bool]
    For further information visit https://errors.pydantic.dev/2.9/v/list_type
defaults.commands.`equity.price.historical`.chart_params
  Input should be a valid list [type=list_type, input_value={'heikin_ashi': True, 'in...'ema': {'length': 150}}}, input_type=dict]
    For further information visit https://errors.pydantic.dev/2.9/v/list_type

After:

from openbb import obb

res = obb.equity.price.historical(symbol="AAPL")
res.show()