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/modules/annotate/diameter_dim.rs

@@ -28,12 +28,24 @@ enum Step {
 
 pub struct DiameterDimensionCommand {
     step: Step,
+    /// Optional text that replaces the measured value (None = measurement).
+    text_override: Option<String>,
+    /// True while the next typed line is captured as the text override.
+    awaiting_text: bool,
+    /// Explicit text rotation in radians (None = follow the UCS/style).
+    text_angle: Option<f64>,
+    /// True while the next typed value is captured as the text angle.
+    awaiting_angle: bool,
 }
 
 impl DiameterDimensionCommand {
     pub fn new() -> Self {
         Self {
             step: Step::CenterPoint,
+            text_override: None,
+            awaiting_text: false,
+            text_angle: None,
+            awaiting_angle: false,
         }
     }
 }
@@ -44,10 +56,18 @@ impl CadCommand for DiameterDimensionCommand {
     }
 
     fn prompt(&self) -> String {
+        if self.awaiting_text {
+            return "DIMDIAMETER  Enter dimension text (blank = measured value):".into();
+        }
+        if self.awaiting_angle {
+            return "DIMDIAMETER  Specify text angle (degrees):".into();
+        }
         match self.step {
             Step::CenterPoint => "DIMDIAMETER  Specify center point:".into(),
             Step::ArcPoint(_) => "DIMDIAMETER  Specify point on circle:".into(),
-            Step::TextPoint { .. } => "DIMDIAMETER  Specify dimension line location:".into(),
+            Step::TextPoint { .. } => {
+                "DIMDIAMETER  Specify dimension line location  [Text/Angle]:".into()
+            }
         }
     }
 
@@ -68,15 +88,79 @@ impl CadCommand for DiameterDimensionCommand {
                 dim.base.insertion_point = v3(pt);
                 dim.leader_length = arc_pt.distance(pt) as f64;
                 dim.base.actual_measurement = dim.measurement();
+                dim.base.user_text = self.text_override.clone();
+                // An explicit text angle overrides the default rotation.
+                if let Some(a) = self.text_angle {
+                    dim.base.text_rotation = a;
+                }
                 CmdResult::CommitAndExit(EntityType::Dimension(Dimension::Diameter(dim)))
             }
         }
     }
 
     fn on_enter(&mut self) -> CmdResult {
+        // A bare Enter while entering override text accepts the measured value.
+        if self.awaiting_text {
+            self.awaiting_text = false;
+            return CmdResult::NeedPoint;
+        }
+        if self.awaiting_angle {
+            self.awaiting_angle = false;
+            return CmdResult::NeedPoint;
+        }
         CmdResult::Cancel
     }
 
+    fn wants_text_input(&self) -> bool {
+        true
+    }
+
+    fn point_step_accepts_keywords(&self) -> bool {
+        // While entering the override text or angle it is a value, not a point step.
+        !self.awaiting_text && !self.awaiting_angle
+    }
+
+    fn wants_text_with_spaces(&self) -> bool {
+        // The override text may contain spaces.
+        self.awaiting_text
+    }
+
+    fn on_text_input(&mut self, text: &str) -> Option<CmdResult> {
+        if self.awaiting_text {
+            let t = text.trim();
+            // Blank (or the "<>" placeholder) keeps the measured value.
+            self.text_override = if t.is_empty() || t == "<>" {
+                None
+            } else {
+                Some(t.to_string())
+            };
+            self.awaiting_text = false;
+            return Some(CmdResult::NeedPoint);
+        }
+        if self.awaiting_angle {
+            let t = text.trim();
+            // Blank clears any explicit angle (follow the default again).
+            self.text_angle = if t.is_empty() {
+                None
+            } else {
+                t.parse::<f64>().ok().map(f64::to_radians)
+            };
+            self.awaiting_angle = false;
+            return Some(CmdResult::NeedPoint);
+        }
+        match text.trim().to_uppercase().as_str() {
+            "T" | "TEXT" | "M" | "MTEXT" => {
+                self.awaiting_text = true;
+                Some(CmdResult::NeedPoint)
+            }
+            "A" | "ANGLE" => {
+                self.awaiting_angle = true;
+                Some(CmdResult::NeedPoint)
+            }
+            _ => None,
+        }
+    }
+
     fn on_mouse_move(&mut self, pt: DVec3) -> Option<WireModel> { let pt = pt.as_vec3();
         match self.step {
             Step::CenterPoint => None,