Fix typing of TransportQueryError.errors to List[GraphQLError]

[magicmark]

Summary

• Changed the type annotation of TransportQueryError.errors from Optional[List[Any]] to Optional[List[GraphQLError]] in both the class attribute and __init__ parameter
• Added from graphql import GraphQLError import to gql/transport/exceptions.py

Motivation

TransportQueryError.errors is populated from ExecutionResult.errors (from graphql-core), which is typed as list[GraphQLError] | None. The current List[Any] annotation loses this type information, making it harder for downstream consumers to work with the errors without casting. This change makes the type annotation accurately reflect the actual data being stored.

Test plan

• All existing tests pass (527 passed, 1 pre-existing failure unrelated to this change)
• flake8, isort, black, and mypy checks pass on the modified file
• No behavioral changes — this is a type annotation-only fix

🤖 Generated with Claude Code

[magicmark]

Closing this PR — after deeper investigation, the typing change isn't correct as-is.

TransportQueryError.errors holds raw dicts at runtime, not GraphQLError objects. All transports (aiohttp, httpx, requests, websockets, phoenix) pass payload.get("errors") (parsed JSON dicts) directly into ExecutionResult, which then gets forwarded to TransportQueryError.errors. Even though ExecutionResult.errors is typed as list[GraphQLError], the actual runtime values are list[dict].

To properly type this as List[GraphQLError], every transport would need to convert the raw error dicts into GraphQLError objects (using GraphQLError(msg, extensions=...) etc). That's a larger change that should be discussed first.

For now, List[Any] accurately reflects the runtime behavior.