refactor(engine): move cmd.rs helpers to cmd/{schema,enabled,params}.rs

crates/engine/src/cmd/enabled.rs

@@ -0,0 +1,38 @@
+use super::*;
+
+// ---------- enablement ----------
+
+pub fn always(_: &Session) -> std::result::Result<(), String> {
+    Ok(())
+}
+
+pub(crate) fn has_comp(s: &Session) -> std::result::Result<(), String> {
+    s.active_comp().map(|_| ()).ok_or_else(|| "no composition is open".into())
+}
+
+pub(crate) fn has_layers(s: &Session) -> std::result::Result<(), String> {
+    has_comp(s)?;
+    if s.state.selected_layers.is_empty() { Err("select a layer first".into()) } else { Ok(()) }
+}
+
+pub(crate) fn has_keys(s: &Session) -> std::result::Result<(), String> {
+    has_comp(s)?;
+    if s.state.selected_keys.is_empty() { Err("select keyframes first".into()) } else { Ok(()) }
+}
+
+pub(crate) fn has_project_selection(s: &Session) -> std::result::Result<(), String> {
+    if s.state.project_selection.is_empty() { Err("select an item in the Project panel first".into()) } else { Ok(()) }
+}
+
+/// Disabled-command enablement (menu entries whose implementation lands with another milestone;
+/// none are left, kept for future stubs).
+#[allow(dead_code)]
+pub(crate) fn not_yet(_: &Session) -> std::result::Result<(), String> {
+    Err("not available yet in EffectCraft".into())
+}
+
+/// `run` of a not-yet-available command.
+#[allow(dead_code)]
+pub(crate) fn not_yet_run(_: &mut Session, _: &Value) -> Result<Value> {
+    Err(EngineError::Other("not available yet in EffectCraft".into()))
+}