GH-32609: [Python] Add internal type system stubs (_types, error, _stubs_typing)

[rok]

Rationale for this change

This is the second in series of PRs adding type annotations to pyarrow and resolving #32609. It builds on top of and should be merged after #48618.

What changes are included in this PR?

This adds:

• _types.pyi - Core type definitions including
• _stubs_typing.pyi - Internal typing protocols and helpers used across stub files
• error.pyi - Exception classes (ArrowException, ArrowInvalid, ArrowIOError, etc.)
• Minimal placeholder stubs - lib.pyi, io.pyi, scalar.pyi - using __getattr__ to allow imports to resolve while deferring to subsequent PRs

Are these changes tested?

Via CI type checks established in #48618.

Are there any user-facing changes?

Users will start seeing some minimal annotated types.

• GitHub Issue: [Python] Type checking support #32609

[dangotbanned]

This isn't the most exciting suggestion, but it's something that constantly frustrates me 😅

Suggested change

	Mask: TypeAlias = (
	Sequence[bool | None]
	| NDArray[np.bool_]
	| BooleanArray
	| ChunkedArray[Any]
	)
	Indices: TypeAlias = (
	Sequence[int | None]
	| NDArray[np.integer[Any]]
	| IntegerArray
	| ChunkedArray[Any]
	)
	from pyarrow import lib
	IntegerType: TypeAlias = (
	lib.Int8Type
	| lib.Int16Type
	| lib.Int32Type
	| lib.Int64Type
	| lib.UInt8Type
	| lib.UInt16Type
	| lib.UInt32Type
	| lib.UInt64Type
	)
	Mask: TypeAlias = (
	Sequence[bool | None]
	| NDArray[np.bool_]
	| lib.Array[lib.Scalar[lib.BoolType]]
	| ChunkedArray[Any]
	)
	Indices: TypeAlias = (
	Sequence[int | None]
	| NDArray[np.integer[Any]]
	| lib.Array[lib.Scalar[IntegerType]]
	| ChunkedArray[Any]
	)

An alternative would just be Array[Any].
Using the concrete subclasses requires the stubs to do a carefully choreographed dance, or the user to typing.cast everywhere - sadly