Retrofit assert_type for Aggregate and Callable #1355

Job	Run time
Run tests with different pydantic versions	3m 17s
Run tests with coverage	2m 51s
Run tests (3.8)	1m 49s
Run tests (3.9)	1m 49s
Run tests (3.12)	1m 54s
Run tests (3.13)	2m 5s
Run linters (pydocstyle)	1m 29s
Run tests (3.11)	1m 49s
Run linters (mypy)	1m 37s
Run tests (3.10)	1m 48s
Run linters (flake8)	1m 32s
Run linters (pylint)	1m 48s
	23m 48s

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