fix: resolve all cargo clippy warnings

- Fix toml version requirement metadata warning
- Replace clone() with std::slice::from_ref()
- Collapse nested if statements
- Add #[allow(dead_code)] to test utility functions
- Fix unused imports and variables in tests
- Use unwrap_or_else instead of expect with format!

wtismycode-core/tests/golden/test_utils.rs

@@ -1,19 +1,21 @@
 //! Test utilities for golden tests
 
 use std::fs;
-use std::path::Path;
 
 /// Read a file and return its contents
+#[allow(dead_code)]
 pub fn read_test_file(path: &str) -> String {
-    fs::read_to_string(path).expect(&format!("Failed to read test file: {}", path))
+    fs::read_to_string(path).unwrap_or_else(|_| panic!("Failed to read test file: {}", path))
 }
 
 /// Write content to a file for testing
+#[allow(dead_code)]
 pub fn write_test_file(path: &str, content: &str) {
-    fs::write(path, content).expect(&format!("Failed to write test file: {}", path))
+    fs::write(path, content).unwrap_or_else(|_| panic!("Failed to write test file: {}", path))
 }
 
 /// Compare two strings and panic if they don't match
+#[allow(dead_code)]
 pub fn assert_strings_equal(actual: &str, expected: &str, message: &str) {
     if actual != expected {
         panic!("{}: Strings do not match\nActual:\n{}\nExpected:\n{}", message, actual, expected);