Repository.resolve_refish can return a Tag, violates docstring and typehint

The typing hint and docstring of Repository.resolve_refish says it returns a Commit object. Actually, it will return a Tag object if given a tag's hex oid. Is this the expected behavior.

For example, in the Linux kernel:

assert pygit2.__version__ == "1.18.0"

# OID of `v6.12.1^{tag}` and v6.12.1^{commit}` in Linux kernel.                 
tag_oid = Oid(hex="a554dea023a451ad985c071f8aae6415f0e274df")   
commit_oid = Oid(hex="d390303b28dabbb91b2d32016a4f72da478733b9")
                                                                
# As documented, symbolic refs resolve to a commit object.
# But the ref target differs from the returned object. Is this the desired behavior?
obj, ref = repo.resolve_refish("v6.12.1")             
assert isinstance(obj, Commit)                                  
assert ref.target != obj.id
assert ref.target == tag_oid                               

# Contrary to the docstring and typing hint, this returns a Tag object.                                                                
obj, ref = repo.resolve_refish(str(tag_oid))                    
assert isinstance(obj, Tag)                                     
assert ref is None

从 Repository.resolve_refish 入口开始，检查符号引用和直接对象 ID 的解析方式。查找涵盖 Commit、Tag 和 ref 目标的现有测试，然后与维护者确认预期的返回契约。只有在文档和类型定义中的行为与已验证的行为一致，并且两个示例都有回归测试覆盖时，才算完成。