Add testcase showing that we do not reveal hover enough info for models

Summary:
I will followup with some basic support for this by encoding some of the most common types.

In case I face any challanges encoding some of the types (I haven't seen any material challanges yet), I am strongly considering that for a field type annotation 'T' fallback be `T || Any` rather than just `Any`. That way, the hover info is still useful and if we face any tricky situations where we can't encode every single type in the conversion table, the hover information would still be useful.

Reviewed By: rchen152

Differential Revision: D87829610

fbshipit-source-id: a6f9689f4db97f06e30efdaf28da3c51c049bc0d

Author: migeed-z

pyrefly/lib/test/pydantic/strict.rs

@@ -102,3 +102,24 @@ Model2(x=0)
 Model2(x='0')  # E: `Literal['0']` is not assignable to parameter `x`
     "#,
 );
+
+pydantic_testcase!(
+    bug = "Revealed type should be more informative",
+    test_lax_mode_coercion,
+    r#"
+from pydantic import BaseModel
+from typing import reveal_type
+
+class Model(BaseModel):
+    x: int = 0
+
+reveal_type(Model.__init__)  # E: revealed type: (self: Model, *, x: Any = ..., **Unknown) -> None
+
+# int field accepts: int, bool, float, str, bytes  
+Model(x=1)
+Model(x=True)
+Model(x=1.0)
+Model(x='123')
+Model(x=b'123')
+    "#,
+);