fix(render): annotative scale representations + model-space linetype scale

Two rendering defects surfaced on the budweiser benchmark drawings, both
tied to a drawing's annotation scale.

Annotative scale representations. A drawing may materialise each annotation
scale as its own object (here a block insert per scale, on a "0 @ <scale>"
layer, each carrying a per-object AcDbContextData bound to one scale).
Nothing filtered them, so every scale drew at once — a 1× copy stacked
under a 10× one. Add annotative::annotative_offscale and apply it in the
three paths that expand block content: the wire block-defn cache, the
resident/top-level visibility gate (model space only — paper viewports use
their per-viewport frozen scale layers), and the exploded-insert hatch/fill
walk (filtered before normalize strips the handle). An object is shown when
a representation matches the current scale; the off-scale ones are hidden.
When the current scale is unsupported by any representation, fall back to
the base "1:1" copy instead of hiding everything (the object must not
vanish) or showing everything (the copies must not stack).

Model-space linetype scale. PSLTSCALE (a paper-space flag) was applied to
model-space linetypes via the annotation scale, so a drawing saved at e.g.
CANNOSCALE 10:1 drew its linetypes 10× off. Thread a `paper_space` flag
through tessellate_entity and gate the PSLTSCALE factor on it, so it only
scales linetypes for content shown inside a paper-space viewport; model
space keeps LTSCALE × CELTSCALE.

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

src/scene/cache/block_cache.rs

@@ -342,6 +342,12 @@ fn build_defn(
         if layer_hidden(doc, &entity.common().layer) {
             continue;
         }
+        // Annotative scale representation: bake only the current scale's copy
+        // into the defn so off-scale representations don't stack (e.g. a 1×
+        // copy under a 10×). See `annotative::annotative_offscale`.
+        if crate::scene::annotative::annotative_offscale(doc, entity.common()) {
+            continue;
+        }
         match entity {
             EntityType::Block(_) | EntityType::BlockEnd(_) => continue,
             // A non-constant ATTDEF is only a template — the insert supplies an