fix(parameters): add NBA Cup and IST season type constants (#620)

[parthashirolkar]

Summary

• Add nba_cup and ist constants to SeasonType parameter class
• Both values resolve to "NBA Cup" and "IST" respectively
• Inherited by all season type parameter classes
• Updated unit tests to validate new constants

Issue

Fixes #620

Background

Users reported that 'IST' season type works with PlayerGameLogs but not TeamDashLineups. The underlying issue was that these season types (NBA Cup/IST) were not available as named constants in the library, forcing users to use raw string literals.

Changes

• src/nba_api/stats/library/parameters.py: Added two new attributes to SeasonType base class
  • nba_cup = "NBA Cup"
  • ist = "IST"
• tests/unit/test_parameters.py: Updated 6 test functions to assert new attributes exist and have correct values

Testing

• All 460 unit tests pass
• Verified constants work with TeamDashLineups and PlayerGameLogs
• Tested both constant values and direct string values (backward compatible)

Usage Example

from nba_api.stats.endpoints import TeamDashLineups
from nba_api.stats.library.parameters import SeasonTypeAllStar

endpoint = TeamDashLineups(
    team_id=1610612739,
    season="2024-25",
    season_type_all_star=SeasonTypeAllStar.nba_cup,
    get_request=True
)

[swar]

awesome, this makes sense. could you please provide URLs here so we can prove that these parameters are valid?

It'll make it easier to verify on here and for us to play around with. I see no problems with this MR other than just confirming the new values.

[parthashirolkar]

@swar, thank you so much for spending the time to review! Just so I understand you correctly, do you mean URLs as in the constructed API calls to nba.com 's API that use this filter?

[swar]

@parthashirolkar Yes that's correct. Basically with these MRs it would be helpful to have a quick URL for reviewers to confirm the new parameters exist.

I'll be sure to add this to the contributions documentation that we have as well.

[parthashirolkar]

@swar Here are some that demonstrate the SeasonType parameters work on NBA.com:

• https://www.nba.com/stats/team/1610612747/lineups?SeasonType=IST
• https://www.nba.com/stats/team/1610612749/lineups?SeasonType=IST&Season=2023-24
• https://www.nba.com/stats/team/1610612747/lineups?SeasonType=NBA%20Cup
  These show that both "IST" and "NBA Cup" are valid SeasonType values accepted by the NBA stats API. The new constants in this allow Python users to reference these values by name instead of hardcoding strings.

Hope this is what you were looking for! 😃