Rename Red Knot (#17820)

crates/ty_python_semantic/resources/mdtest/boolean/short_circuit.md

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+# Short-Circuit Evaluation
+
+## Not all boolean expressions must be evaluated
+
+In `or` expressions, if the left-hand side is truthy, the right-hand side is not evaluated.
+Similarly, in `and` expressions, if the left-hand side is falsy, the right-hand side is not
+evaluated.
+
+```py
+def _(flag: bool):
+    if flag or (x := 1):
+        # error: [possibly-unresolved-reference]
+        reveal_type(x)  # revealed: Literal[1]
+
+    if flag and (x := 1):
+        # error: [possibly-unresolved-reference]
+        reveal_type(x)  # revealed: Literal[1]
+```
+
+## First expression is always evaluated
+
+```py
+def _(flag: bool):
+    if (x := 1) or flag:
+        reveal_type(x)  # revealed: Literal[1]
+
+    if (x := 1) and flag:
+        reveal_type(x)  # revealed: Literal[1]
+```
+
+## Statically known truthiness
+
+```py
+if True or (x := 1):
+    # error: [unresolved-reference]
+    reveal_type(x)  # revealed: Unknown
+
+if True and (x := 1):
+    reveal_type(x)  # revealed: Literal[1]
+```
+
+## Later expressions can always use variables from earlier expressions
+
+```py
+def _(flag: bool):
+    flag or (x := 1) or reveal_type(x)  # revealed: Never
+
+    # error: [unresolved-reference]
+    flag or reveal_type(y) or (y := 1)  # revealed: Unknown
+```
+
+## Nested expressions
+
+```py
+def _(flag1: bool, flag2: bool):
+    if flag1 or ((x := 1) and flag2):
+        # error: [possibly-unresolved-reference]
+        reveal_type(x)  # revealed: Literal[1]
+
+    if ((y := 1) and flag1) or flag2:
+        reveal_type(y)  # revealed: Literal[1]
+
+    # error: [possibly-unresolved-reference]
+    if (flag1 and (z := 1)) or reveal_type(z):  # revealed: Literal[1]
+        # error: [possibly-unresolved-reference]
+        reveal_type(z)  # revealed: Literal[1]
+```