feat: complete wgcloak v1 transports

fuzz/fuzz_targets/fuzz_config_toml.rs

@@ -0,0 +1,15 @@
+#![no_main]
+
+use libfuzzer_sys::fuzz_target;
+use wgcloak::config::Config;
+
+const MAX_INPUT: usize = 64 * 1024;
+
+fuzz_target!(|input: &[u8]| {
+    let input = &input[..input.len().min(MAX_INPUT)];
+    // Parsing only: Config::from_str never reads secret files. Validation is
+    // intentionally not called because it may resolve file-backed secrets.
+    if let Ok(text) = std::str::from_utf8(input) {
+        let _ = Config::from_str(text);
+    }
+});