Update all dependencies to latest versions

wasmtime 31→43, wasm-encoder/wasmparser 0.228→0.246, rustyline 15→18.

API migrations: F64Const now takes Ieee64 wrapper, wasmtime has own
Error type (wasmtime::bail! in host closures), cache_config_load_default
removed. Add performance regression limits to benchmark tests.

crates/core/src/outer.rs

@@ -282,8 +282,6 @@ impl ForthVM {
     pub fn new_with_config(wafer_config: WaferConfig) -> anyhow::Result<Self> {
         let mut config = wasmtime::Config::new();
         config.cranelift_nan_canonicalization(false);
-        // Best-effort module caching
-        let _ = config.cache_config_load_default();
         let engine = Engine::new(&config)?;
         let output = Arc::new(Mutex::new(String::new()));