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-cli/src/main.rs

@@ -34,6 +34,8 @@
 //! `<comp>` is a comp id or name (`-` = the active comp); `<layer>` an id, `#n` or name; `<value>`
 //! is JSON (`50`, `[960,540]`, `"#ff0000"`) or a bare string. See `docs/agents.md`.
 
+#![deny(clippy::unwrap_used, clippy::expect_used, clippy::panic, clippy::unimplemented, clippy::todo, clippy::unreachable)]
+
 use effectcraft_automation::tools::{self, Reply};
 use effectcraft_automation::{Backend, McpServer};
 use serde_json::{Value, json};