Harden parametric sketch constraints

src/app/commands/draw.rs

@@ -963,9 +963,7 @@ impl OpenCADStudio {
                 }
             }
 
-            // ── Constraints (persistent: added to the scope's SketchConstraintSet,
-            // solved via Scene::bump_entities, re-solved on every later edit —
-            // see docs/parametric_system_design.md §6.1) ──
+            // ── Persistent constraints ────────────────────────────────────
             "HCONSTRAINT" | "VCONSTRAINT" | "FXCONSTRAINT" => {
                 let handles = self.tabs[i].scene.selected_handles_in_order();
                 if handles.is_empty() {

src/app/commands/mod.rs

@@ -298,10 +298,12 @@ pub fn start_allowed(cmd: &str) -> bool {
             | "PERF"
             | "CUI"
             | "ALIASEDIT"
-            | "OPTIONS"
-            | "OP"
             | "CUILOAD"
             | "CUIIMPORT"
+            // The start page already offers Options as a button, so the
+            // command that opens the same dialog belongs here too.
+            | "OPTIONS"
+            | "OP"
     )
 }
 

src/app/commands/view.rs

@@ -240,30 +240,23 @@ impl OpenCADStudio {
                 return Some(Task::done(Message::AliasEditorOpen));
             }
 
-            // ── OPTIONS — app preferences dialog ────────────────────────────
-            // Registered for autocomplete (`commands/mod.rs`'s "one-shot
-            // commands" list) but had no actual dispatch arm anywhere — the
-            // Start-tab welcome screen's "Options" button emits
-            // `Message::OptionsOpen` directly and was the only way to reach
-            // it. Found while live-testing the new UI-scale setting (nothing
-            // to do with that feature itself, just discovered along the
-            // way). "OP" is AutoCAD's own short alias for this command.
+            // ── CUI — keyboard shortcut / key-binding editor ───────────────
+            "CUI" => {
+                return Some(Task::done(Message::ShortcutsPanelOpen));
+            }
+
+            // ── OPTIONS / OP — the preferences dialog ──────────────────────
+            // Both names were registered for autocomplete but never dispatched,
+            // so typing either one answered "Unknown command" and the dialog
+            // could only be reached from the button on the start page.
             "OPTIONS" | "OP" => {
                 return Some(Task::done(Message::OptionsOpen));
             }
 
-            // ── PARAMETERS — named-parameter/expression table editor ───────
-            // `docs/named_parameters_design.md` stage 4. AutoCAD's own
-            // command name for the equivalent feature (Parameters Manager).
             "PARAMETERS" => {
                 return Some(Task::done(Message::NamedParametersOpen));
             }
 
-            // ── CUI — keyboard shortcut / key-binding editor ───────────────
-            "CUI" => {
-                return Some(Task::done(Message::ShortcutsPanelOpen));
-            }
-
             // CUIEXPORT <path> — write the keyboard-shortcut customizations
             // (the drawing-independent CUI data) to a plain "KEY COMMAND" file.
             "CUIEXPORT" => {