fix(mleader): text left of its landing attaches by its right edge

The text was placed by its alignment rather than its attachment point,
so text on the left of the landing ran over the leader. It now attaches
by the attachment point, and putting the text on a side (on creation or
by a grip) turns left- or right-justified text to read away from the
leader.

Fixes #1646

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

src/entities/multileader.rs

@@ -703,11 +703,7 @@ fn apply_grip(
             } else {
                 old_sign
             };
-            ml.context.text_attachment_point = if new_sign >= 0.0 {
-                codec::entities::multileader::TextAttachmentPointType::Left
-            } else {
-                codec::entities::multileader::TextAttachmentPointType::Right
-            };
+            set_mleader_text_side(ml, new_sign >= 0.0);
             set_mleader_text_location(ml, target + axis * (new_sign * (dogleg + gap)));
 
             if let Some(root) = ml.context.leader_roots.first_mut() {
@@ -2226,10 +2222,10 @@ impl MultiLeaderTess for MultiLeader {
             };
             // The context's attachment point exists in every DWG version;
             // the entity-level copy only exists from R2010 on.
-            let h_anchor: f32 = match ctx.text_alignment {
-                TextAlignmentType::Left => 0.0,
-                TextAlignmentType::Center => 0.5,
-                TextAlignmentType::Right => 1.0,
+            let h_anchor: f32 = match ctx.text_attachment_point {
+                codec::entities::multileader::TextAttachmentPointType::Left => 0.0,
+                codec::entities::multileader::TextAttachmentPointType::Center => 0.5,
+                codec::entities::multileader::TextAttachmentPointType::Right => 1.0,
             };
             // Pick the vertical-anchor attachment based on text_attachment_direction:
             //   Horizontal — leader attaches left/right; use ml.text_left_attachment
@@ -2715,3 +2711,23 @@ mod tests {
         );
     }
 }
+
+/// Put the text on the right (`to_right`) or left of its landing: the text
+/// block attaches by its near edge, and left- or right-justified text turns
+/// to read away from the leader. Centred text stays centred.
+pub(crate) fn set_mleader_text_side(ml: &mut MultiLeader, to_right: bool) {
+    use codec::entities::multileader::TextAttachmentPointType;
+    let (attachment, alignment) = if to_right {
+        (TextAttachmentPointType::Left, TextAlignmentType::Left)
+    } else {
+        (TextAttachmentPointType::Right, TextAlignmentType::Right)
+    };
+    ml.text_attachment_point = attachment;
+    ml.context.text_attachment_point = attachment;
+    if ml.context.text_alignment != TextAlignmentType::Center {
+        ml.context.text_alignment = alignment;
+    }
+    if ml.text_alignment != TextAlignmentType::Center {
+        ml.text_alignment = alignment;
+    }
+}

src/modules/annotate/mleader_cmd.rs

@@ -693,12 +693,7 @@ fn build_mleader(
     let to_right = (elbow_pt - arrow_pt).dot(ux.as_dvec3()) >= 0.0;
     let sign = if to_right { 1.0 } else { -1.0 };
     let landing = ux * (sign as f32);
-    ml.context.text_attachment_point =
-        if to_right {
-            codec::entities::multileader::TextAttachmentPointType::Left
-        } else {
-            codec::entities::multileader::TextAttachmentPointType::Right
-        };
+    crate::entities::multileader::set_mleader_text_side(&mut ml, to_right);
 
     ml.context.text_rotation = (ux.y as f64).atan2(ux.x as f64);
     ml.context.text_direction = Vector3::new(ux.x as f64, ux.y as f64, 0.0);