Never crash: deny panic lints in the already-clean crates and apps

These crates have no production panic sites: add the deny attribute so they stay clean
(geom, color, model, automation, host, export, plugin, and the desktop, CLI and web apps). The
plugin's wasm-only test module gets a separate cfg(test) attribute so clippy recognises it as
test code.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

apps/effectcraft-web/src/lib.rs

@@ -20,6 +20,8 @@
 //!
 //! [`store`] is portable (unit-tested natively); everything else is `wasm32`-only.
 
+#![deny(clippy::unwrap_used, clippy::expect_used, clippy::panic, clippy::unimplemented, clippy::todo, clippy::unreachable)]
+
 pub mod store;
 
 #[cfg(target_arch = "wasm32")]