feat(commands): integrate standard CAD commands and fix behavior gaps

Broad pass over the command set: integrate missing commands, wire
previously-unreachable ribbon/menu buttons, and correct name/behaviour
mismatches. Every UI command token now resolves (real handler where the
infrastructure exists, an honest "not yet implemented" status otherwise).

New commands:
- Draw: 3DPOLY, 2D solid (SO/SOLID2D), HELIX, TRACE, SKETCH, DIMCENTER
  (DCE/CENTERMARK)
- Modify/inquiry: REVERSE, MEASUREGEOM (MEA), DBLIST
- Data/manage: BASE, OVERKILL (exact-duplicate removal), AUDIT (read-only
  integrity report), SETVAR (system-variable get/set), SCRIPT (.scr runner),
  FINDNONPURGEABLE

Behaviour fixes:
- LINE and SPLINE gain Close/Undo; AREA computes area/perimeter in f64
  (correct at large coordinates)
- ATTEDIT/ATE unified so the alias and the ribbon button open the
  interactive editor; -ATTEDIT is the command-line form
- Linear/aligned/radius/diameter dimensions gain a text override (Text) and
  text angle (Angle) option
- INSERT gains Scale/Rotate options; COPY gains an Array option
- LINETYPE SET sets the current entity linetype; SETBYLAYER resets overrides
- UNDO accepts a step count

Integrations: standard dimension/block aliases (DLI/DRA/DAN, BMAKE,
EXPORTPDF, DDIM), drafting-aid and screen toggles (GRID/SNAP/POLAR/OSNAP/
DSETTINGS/CLEANSCREEN/QUICKPROPERTIES), viewport tiling
(CASCADE/HORIZONTAL/VERTICAL/VPJOIN), and customization entry points
(CUI/ALIASEDIT).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/app/commands/draw.rs

@@ -52,12 +52,21 @@ impl OpenCADStudio {
                 self.tabs[i].active_cmd = Some(Box::new(cmd));
             }
 
-            // ATTEDIT — list or edit attribute values on selected Insert entities.
+            // Command-line attribute editing on selected Insert entities. Bare
+            // ATTEDIT and the ATE alias launch the interactive editor instead
+            // (see the ATTEDIT arm in the inquiry family); the dash form is the
+            // command-line entry point.
             // Usage:
-            //   ATTEDIT           — list all attributes on selected Insert(s)
-            //   ATTEDIT <tag> <v> — set the value of attribute <tag> to <v>
-            cmd if cmd == "ATTEDIT" || cmd.starts_with("ATTEDIT ") => {
-                let rest = cmd.trim_start_matches("ATTEDIT").trim();
+            //   -ATTEDIT          — list all attributes on selected Insert(s)
+            //   ATTEDIT <tag> <v> — quick-set attribute <tag> to <v>
+            cmd if cmd.starts_with("ATTEDIT ")
+                || cmd == "-ATTEDIT"
+                || cmd.starts_with("-ATTEDIT ") =>
+            {
+                let rest = cmd
+                    .trim_start_matches("-ATTEDIT")
+                    .trim_start_matches("ATTEDIT")
+                    .trim();
                 let parts: Vec<&str> = rest.splitn(2, char::is_whitespace).collect();
                 let selected_handles: Vec<acadrust::Handle> = self.tabs[i]
                     .scene
@@ -340,6 +349,64 @@ impl OpenCADStudio {
                 self.tabs[i].active_cmd = Some(Box::new(new_cmd));
             }
 
+            "3DPOLY" => {
+                use crate::modules::draw::draw::poly3d::Poly3dCommand;
+                let new_cmd = Poly3dCommand::new();
+                self.command_line.push_info(&new_cmd.prompt());
+                self.tabs[i].active_cmd = Some(Box::new(new_cmd));
+            }
+
+            // 2D filled solid. Reached via SO / SOLID2D — the bare SOLID verb is
+            // currently the shaded-display toggle (token collision tracked).
+            "SO" | "SOLID2D" => {
+                use crate::modules::draw::draw::solid2d::Solid2dCommand;
+                let new_cmd = Solid2dCommand::new();
+                self.command_line.push_info(&new_cmd.prompt());
+                self.tabs[i].active_cmd = Some(Box::new(new_cmd));
+            }
+
+            "HELIX" => {
+                use crate::modules::draw::draw::helix::HelixCommand;
+                let new_cmd = HelixCommand::new();
+                self.command_line.push_info(&new_cmd.prompt());
+                self.tabs[i].active_cmd = Some(Box::new(new_cmd));
+            }
+
+            "TRACE" => {
+                use crate::modules::draw::draw::trace::TraceCommand;
+                let new_cmd = TraceCommand::new();
+                self.command_line.push_info(&new_cmd.prompt());
+                self.tabs[i].active_cmd = Some(Box::new(new_cmd));
+            }
+
+            "DIMCENTER" | "DCE" | "CENTERMARK" => {
+                use crate::modules::draw::draw::dimcenter::DimCenterCommand;
+                let new_cmd = DimCenterCommand::new();
+                self.command_line.push_info(&new_cmd.prompt());
+                self.tabs[i].active_cmd = Some(Box::new(new_cmd));
+            }
+
+            "SKETCH" => {
+                use crate::modules::draw::draw::sketch::SketchCommand;
+                let new_cmd = SketchCommand::new();
+                self.command_line.push_info(&new_cmd.prompt());
+                self.tabs[i].active_cmd = Some(Box::new(new_cmd));
+            }
+
+            "REVERSE" => {
+                use crate::modules::draw::modify::reverse::ReverseCommand;
+                let new_cmd = ReverseCommand::new();
+                self.command_line.push_info(&new_cmd.prompt());
+                self.tabs[i].active_cmd = Some(Box::new(new_cmd));
+            }
+
+            "MEASUREGEOM" | "MEA" => {
+                use crate::modules::draw::inquiry::measuregeom::MeasureGeomCommand;
+                let new_cmd = MeasureGeomCommand::new();
+                self.command_line.push_info(&new_cmd.prompt());
+                self.tabs[i].active_cmd = Some(Box::new(new_cmd));
+            }
+
             // ── Modify commands ────────────────────────────────────────────
             "MOVE" | "M" => {
                 let handles: Vec<_> = self.tabs[i]