This patch fixes a bug where resolving recursive forward references in
"from_type()" (such as "A = list[Union["A", str]]", added in
v6.152.11) could recurse until it hit the interpreter's recursion
limit before falling back to a deferred strategy. Because this
depended on the ambient stack depth, it occasionally surfaced as a
spurious "RecursionError" or other flaky failure. We now break the
cycle eagerly by deferring, so resolution uses a small and constant
amount of stack regardless of how deeply nested the reference is.
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