M3.42: Appearance editing depth — drag effect rows to reorder them or move them into/out of fills and strokes (Alt copies), click an effect name to edit it in its prefilled dialog, choosing an applied effect asks to edit it or add another, Show All Hidden Attributes, multi-select and Alt-drag duplicate of fills/strokes, drag the thumbnail onto art to copy the appearance, stroke rows note brush/Dashed/profile, Shift-click a chip for the mixer, Properties fx opens the effect menu

Engine: effect.move {from, to, fromItem?, toItem?, copy?}; appearance.showAllHidden;
appearance.duplicateItem takes to? and indices?; appearance.removeItem takes indices?;
Appearance::has_hidden/show_all. UI: effect.dialog takes index? (edit in place via
effect.setParams) and opens the effectExists question for an effect already in the list.

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

crates/engine/src/cmd/effectcmd.rs

@@ -10,7 +10,7 @@ use vectorcraft_doc::{Effect, Node, NodeKind};
 use vectorcraft_geom::{FillRule, PathData};
 use vectorcraft_render::effects;
 
-use super::appearance::{ItemTarget, appearance_targets, index_param, item_target};
+use super::appearance::{ItemTarget, appearance_targets, index_param, item_target, item_target_at};
 use super::*;
 
 pub fn specs() -> Vec<CommandSpec> {
@@ -69,6 +69,15 @@ pub fn specs() -> Vec<CommandSpec> {
             has_selection,
             duplicate
         ),
+        cmd!(
+            "effect.move",
+            "Move Effect",
+            [],
+            None,
+            "{from: int (position in the source list), to: int (its position in the destination list afterwards), fromItem?: appearance item index|null (the source list: that fill/stroke's effects, null the object's; omitted: the active item, else the object's), toItem?: item index|null (the destination list; default: the source list), copy?: bool (copy instead of move, as Alt-dragging the row), ids?: [..]} reorder an effect or move it between the object and its fills/strokes, as one undo step → {ids, index, item}",
+            has_selection,
+            move_effect
+        ),
     ]
 }
 
@@ -175,6 +184,38 @@ fn duplicate(s: &mut Session, p: &Value) -> Result<Value> {
     Ok(json!({ "ids": ids_json(&ids) }))
 }
 
+fn move_effect(s: &mut Session, p: &Value) -> Result<Value> {
+    const C: &str = "effect.move";
+    let from = index_param(p, "from", C)?;
+    let to = index_param(p, "to", C)?;
+    let src = item_target_at(s, p, "fromItem", C)?;
+    let dst = if p.get("toItem").is_some() { item_target_at(s, p, "toItem", C)? } else { src };
+    let copy = p.get("copy").and_then(Value::as_bool).unwrap_or(false);
+    let roots = appearance_targets(s, p)?;
+    // Where the effect landed in the first object.
+    let mut landed = None;
+    let ids = s.edit(if copy { "Duplicate Effect" } else { "Move Effect" }, |d, _| {
+        let mut done = vec![];
+        for id in &roots {
+            let Some(n) = d.node_mut(*id) else { continue };
+            let (si, di) = (src.effects_item(&n.appearance, C)?, dst.effects_item(&n.appearance, C)?);
+            let Some(fx) = n.appearance.effects_mut(si).filter(|fx| from < fx.len()) else { continue };
+            let e = if copy { fx[from].clone() } else { fx.remove(from) };
+            let Some(fx) = n.appearance.effects_mut(di) else { continue };
+            let at = to.min(fx.len());
+            fx.insert(at, e);
+            landed.get_or_insert((at, di));
+            done.push(*id);
+        }
+        if done.is_empty() {
+            return Err(EngineError::Other(format!("{C}: no effect at index {from}")));
+        }
+        Ok(done)
+    })?;
+    let (index, item) = landed.unzip();
+    Ok(json!({ "ids": ids_json(&ids), "index": index, "item": item.flatten() }))
+}
+
 fn set_params(s: &mut Session, p: &Value) -> Result<Value> {
     const C: &str = "effect.setParams";
     let index = index_param(p, "index", C)?;