Refactor: Remove unnecessary casts and tighten type checking (#26625)

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api/pyrightconfig.json

@@ -25,7 +25,6 @@
   "reportMissingParameterType": "hint",
   "reportMissingTypeArgument": "hint",
   "reportUnnecessaryComparison": "hint",
-  "reportUnnecessaryCast": "hint",
   "reportUnnecessaryIsInstance": "hint",
   "reportUntypedFunctionDecorator": "hint",