Save as mesh: one dialog for STL and 3MF, with Send to slicer (#1272)

One docked Save as mesh dialog replaces Export STL / 3MF / 3MF with face tags, with an optional Send to slicer that lists the slicers installed on this machine. Engine: file.save_mesh and file.slicers; the Convert Mesh dialog goes (mesh.convert and the MeshConvert feature stay, so existing designs open). Strings in all catalogs; screenshots in the PR. Checked on main + this branch: cargo check --workspace, the engine slicer/mesh/file tests, the UI catalog and menu tests and scenario s14 (the one local colour-token failure is epaint's TexturesDelta panic, which main shows on this machine too).

crates/ui-egui/src/dialogs_surface.rs

@@ -45,9 +45,6 @@ pub enum Surf {
     Stitch {
         tolerance: String,
     },
-    ConvertMesh {
-        tolerance: String,
-    },
     Thicken {
         thickness: String,
         symmetric: bool,
@@ -79,7 +76,6 @@ impl Surf {
             Surf::Offset { .. } => "OFFSET SURFACE",
             Surf::Ruled { .. } => "RULED SURFACE",
             Surf::Stitch { .. } => "STITCH",
-            Surf::ConvertMesh { .. } => "CONVERT MESH",
             Surf::Thicken { .. } => "THICKEN",
             Surf::Extend { .. } => "EXTEND",
             Surf::Trim => "TRIM",
@@ -124,7 +120,6 @@ fn inputs(k: &Surf) -> Vec<SelInput> {
             vec![SelInput::new("Edges", EDGES, true), SelInput::new("Reference face", FACES, false), SelInput::new("Direction", AXES | EDGES, false)]
         }
         Surf::Stitch { .. } => vec![SelInput::new("Surfaces", BODIES, true)],
-        Surf::ConvertMesh { .. } => vec![SelInput::new("Mesh body", BODIES, false)],
         Surf::Thicken { .. } => vec![SelInput::new("Surfaces", BODIES, true)],
         Surf::Extend { .. } => vec![SelInput::new("Edges", EDGES, true)],
         Surf::Trim => vec![
@@ -150,7 +145,6 @@ pub fn start(_app: &SolveApp, id: &str) -> Option<(Kind, Vec<SelInput>)> {
         "surface.offset" => Surf::Offset { distance: "2 mm".into(), chain: false },
         "surface.ruled" => Surf::Ruled { distance: "10 mm".into(), mode: 0, angle: "5 deg".into(), flip: false, round: false },
         "surface.stitch" => Surf::Stitch { tolerance: String::new() },
-        "mesh.convert" => Surf::ConvertMesh { tolerance: "0.05 mm".into() },
         "surface.thicken" => Surf::Thicken { thickness: "2 mm".into(), symmetric: false, operation: 0 },
         "surface.extend" => Surf::Extend { distance: "10 mm".into() },
         "surface.trim" => Surf::Trim,
@@ -166,7 +160,7 @@ pub fn start(_app: &SolveApp, id: &str) -> Option<(Kind, Vec<SelInput>)> {
 pub fn rows(ui: &mut egui::Ui, k: &mut Surf) -> bool {
     let mut enter = false;
     match k {
-        Surf::Stitch { tolerance } | Surf::ConvertMesh { tolerance } => {
+        Surf::Stitch { tolerance } => {
             row_label(ui, "Tolerance");
             let r = ui.add(egui::TextEdit::singleline(tolerance).hint_text("tight"));
             crate::params_dialog::complete(ui, &r, tolerance);
@@ -469,11 +463,6 @@ pub fn commands(app: &SolveApp, k: &Surf, inputs: &[SelInput], extra: &Map<Strin
             }
             ("surface.stitch", p)
         }
-        Surf::ConvertMesh { tolerance } => {
-            need(0, "a closed mesh body")?;
-            let body = bodies(inputs, 0).into_iter().next().ok_or("select a mesh body")?;
-            ("mesh.convert", json!({"body":body,"tolerance":tolerance}))
-        }
         Surf::Thicken { thickness, symmetric, operation } => {
             need(0, "the surfaces to thicken")?;
             (
@@ -661,9 +650,6 @@ pub fn for_feature(app: &SolveApp, kind: &FeatureKind, frame: &Mat) -> Option<(K
             Surf::Stitch { tolerance: if tolerance.trim() == "0" { String::new() } else { tolerance.clone() } },
             vec![bodies.iter().map(|n| Sel::Body { name: n.clone() }).collect()],
         ),
-        FeatureKind::MeshConvert { body, tolerance } => {
-            (Surf::ConvertMesh { tolerance: tolerance.clone() }, vec![vec![Sel::Body { name: body.clone() }]])
-        }
         FeatureKind::Thicken { bodies, thickness, symmetric, operation, .. } => (
             Surf::Thicken { thickness: thickness.clone(), symmetric: *symmetric, operation: op_index(operation) },
             vec![bodies.iter().map(|n| Sel::Body { name: n.clone() }).collect()],