[flake8-simplify] Fix truthiness assumption for non-iterable arguments in tuple/list/set calls (SIM222, SIM223) (#21479)

## Summary

Fixes false positives in SIM222 and SIM223 where truthiness was
incorrectly assumed for `tuple(x)`, `list(x)`, `set(x)` when `x` is not
iterable.

Fixes #21473.

## Problem

`Truthiness::from_expr` recursively called itself on arguments to
iterable initializers (`tuple`, `list`, `set`) without checking if the
argument is iterable, causing false positives for cases like `tuple(0)
or True` and `tuple("") or True`.

## Approach

Added `is_definitely_not_iterable` helper and updated
`Truthiness::from_expr` to return `Unknown` for non-iterable arguments
(numbers, booleans, None) and string literals when called with iterable
initializers, preventing incorrect truthiness assumptions.

## Test Plan

Added test cases to `SIM222.py` and `SIM223.py` for `tuple("")`,
`tuple(0)`, `tuple(1)`, `tuple(False)`, and `tuple(None)` with `or True`
and `and False` patterns.

---------

Co-authored-by: Brent Westbrook <brentrwestbrook@gmail.com>

crates/ruff_python_ast/src/helpers.rs

@@ -1322,14 +1322,22 @@ impl Truthiness {
                             && arguments.keywords.is_empty()
                         {
                             // Ex) `list([1, 2, 3])`
-                            // For tuple(generator), we can't determine statically if the result will
-                            // be empty or not, so return Unknown. The generator itself is truthy, but
-                            // tuple(empty_generator) is falsy. ListComp and SetComp are handled by
-                            // recursing into Self::from_expr below, which returns Unknown for them.
-                            if argument.is_generator_expr() {
-                                Self::Unknown
-                            } else {
-                                Self::from_expr(argument, is_builtin)
+                            match argument {
+                                // Return Unknown for types with definite truthiness that might
+                                // result in empty iterables (t-strings and generators) or will
+                                // raise a type error (non-iterable types like numbers, booleans,
+                                // None, etc.).
+                                Expr::NumberLiteral(_)
+                                | Expr::BooleanLiteral(_)
+                                | Expr::NoneLiteral(_)
+                                | Expr::EllipsisLiteral(_)
+                                | Expr::TString(_)
+                                | Expr::Lambda(_)
+                                | Expr::Generator(_) => Self::Unknown,
+                                // Recurse for all other types - collections, comprehensions, variables, etc.
+                                // StringLiteral, FString, and BytesLiteral recurse because Self::from_expr
+                                // correctly handles their truthiness (checking if empty or not).
+                                _ => Self::from_expr(argument, is_builtin),
                             }
                         } else {
                             Self::Unknown