Implement template strings (#17851)

This PR implements template strings (t-strings) in the parser and
formatter for Ruff.

Minimal changes necessary to compile were made in other parts of the code (e.g. ty, the linter, etc.). These will be covered properly in follow-up PRs.

crates/ruff_python_ast/src/python_version.rs

@@ -59,6 +59,13 @@ impl PythonVersion {
         Self::PY313
     }
 
+    /// The latest Python version supported in preview
+    pub fn latest_preview() -> Self {
+        let latest_preview = Self::PY314;
+        debug_assert!(latest_preview >= Self::latest());
+        latest_preview
+    }
+
     pub const fn latest_ty() -> Self {
         // Make sure to update the default value for  `EnvironmentOptions::python_version` when bumping this version.
         Self::PY313