feat(annotative): scale text/dims/tables/blocks at the annotation scale + editable property pickers

Render: annotative-ness is resolved centrally in scene::annotative::is_annotative
(per-object context dictionary, legacy XDATA, or annotative style) so the bake and
the properties panel agree. Text, dimensions, tables and blocks now display at the
current annotation scale in model space. An annotative block scales as one uniform
unit about its insertion point — its internal geometry and attributes are carried by
that scale instead of being scaled individually, fixing the block-attribute size
regression. Tables scale their column/row/margin geometry.

Properties: the handle- and flag-backed rows are now editable pickers — MLEADER
multileader style / text style / arrowhead / leader linetype, General Material, and
Plot style (named plot-style mode only; the color-dependent mode stays read-only,
which is correct). A picked name is resolved back to its handle in the update loop,
where the document is in scope. Annotative Yes/No and the annotation-scale row are
shown per object.

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

src/scene/annotative.rs

@@ -0,0 +1,98 @@
+//! Shared annotative-object detection + annotation-scale resolution.
+//!
+//! Both the Properties panel (Annotative row / applied scale name) and the
+//! tessellation bake (which scales annotative content by the current annotation
+//! scale) must agree on *which* entities are annotative — so that logic lives
+//! here, once. An entity is annotative if it carries a per-object annotation
+//! context, the legacy annotative XDATA, or an annotative style.
+
+use acadrust::entities::{EntityCommon, EntityType};
+use acadrust::objects::{Dictionary, ObjectType};
+use acadrust::{CadDocument, Handle};
+
+/// Resolve a handle to a `Dictionary` object, if it is one.
+pub fn as_dict(doc: &CadDocument, handle: Handle) -> Option<&Dictionary> {
+    match doc.objects.get(&handle) {
+        Some(ObjectType::Dictionary(d)) => Some(d),
+        _ => None,
+    }
+}
+
+/// Does a style name resolve to `name` (or to "Standard" when `name` is blank)?
+fn name_matches(style_name: &str, name: &str) -> bool {
+    style_name.eq_ignore_ascii_case(name)
+        || (name.trim().is_empty() && style_name.eq_ignore_ascii_case("Standard"))
+}
+
+fn text_style_annotative(doc: &CadDocument, name: &str) -> bool {
+    doc.text_styles
+        .iter()
+        .find(|s| name_matches(&s.name, name))
+        .is_some_and(|s| s.annotative)
+}
+
+fn dim_style_annotative(doc: &CadDocument, name: &str) -> bool {
+    doc.dim_styles
+        .iter()
+        .find(|s| name_matches(&s.name, name))
+        .is_some_and(|s| s.annotative)
+}
+
+fn mleader_style_annotative(doc: &CadDocument, handle: Option<Handle>) -> bool {
+    let Some(h) = handle else {
+        return false;
+    };
+    doc.objects.iter().any(|(oh, o)| {
+        matches!(o, ObjectType::MultiLeaderStyle(s) if *oh == h && s.is_annotative)
+    })
+}
+
+fn table_style_annotative(doc: &CadDocument, handle: Option<Handle>) -> bool {
+    let Some(h) = handle else {
+        return false;
+    };
+    doc.objects
+        .iter()
+        .any(|(oh, o)| matches!(o, ObjectType::TableStyle(s) if *oh == h && s.annotative))
+}
+
+/// Whether an object carries a per-object annotation context — its extension
+/// dictionary holds an `AcDbContextDataManager`. This catches objects that are
+/// annotative by context even when their style is not.
+fn has_context_manager(doc: &CadDocument, common: &EntityCommon) -> bool {
+    common
+        .xdictionary_handle
+        .and_then(|h| as_dict(doc, h))
+        .map(|d| {
+            d.entries
+                .iter()
+                .any(|(k, _)| k.eq_ignore_ascii_case("AcDbContextDataManager"))
+        })
+        .unwrap_or(false)
+}
+
+/// Whether an entity participates in annotation scaling.
+pub fn is_annotative(doc: &CadDocument, entity: &EntityType) -> bool {
+    // Per-object annotation context (works regardless of style).
+    if has_context_manager(doc, entity.common()) {
+        return true;
+    }
+    // Legacy annotative XDATA markers.
+    let xd = &entity.common().extended_data;
+    if xd.get_record("AcAnnoPO").is_some() || xd.get_record("AcAnnotativeData").is_some() {
+        return true;
+    }
+    // Annotative via the assigned style (or the entity's own flag).
+    match entity {
+        EntityType::Text(t) => text_style_annotative(doc, &t.style),
+        EntityType::MText(t) => t.is_annotative || text_style_annotative(doc, &t.style),
+        EntityType::Dimension(d) => dim_style_annotative(doc, &d.base().style_name),
+        EntityType::Leader(l) => dim_style_annotative(doc, &l.dimension_style),
+        EntityType::MultiLeader(ml) => {
+            ml.enable_annotation_scale || mleader_style_annotative(doc, ml.style_handle)
+        }
+        EntityType::Table(t) => table_style_annotative(doc, t.table_style_handle),
+        _ => false,
+    }
+}
+