Merge branch 'main' into feature/parametric-constraint-system

Brings in 54 commits from origin/main: a selection-performance overhaul,
surface thickening, GPU-native wide/tapered stroke rendering, continued
ocs_doc_api evolution, and assorted fixes/polish (block double-click
editing, DWG hatch/database repair, clipboard, collapsible Properties
sections).

Six real conflicts, all where this branch had independently re-applied
a fix upstream later revised or already carried natively:

- src/app/automation.rs, src/app/command_driver.rs: combined both
  sides — kept this branch's sketch-constraint/named-parameter loading
  on "new"/"open", adopted main's Scene::clear()/material_base_dir and
  its newer rebuild_derived_caches() over the older bump_geometry().
  Scene::clear() (src/scene/entity.rs) now also resets
  sketch_constraints/named_parameters, so every caller gets this for
  free instead of each call site repeating it.
- src/io/mod.rs, src/scene/render_graph.rs: adopted main's design
  outright (commit 973af87d, authored by Hakan directly) — a large
  MINSERT is no longer purged as "corrupt" at load, only its rendering
  is bounded, preserving the source data. This branch's own earlier
  design (reject at load) predates that revision.
- src/scene/pipeline/mesh_gpu.rs: adopted main's valid_rgba_size()
  guard (a real robustness improvement over this branch's version).
- src/snap.rs: replaced wholesale with main's version — this branch's
  copy was an explicit verbatim snapshot from an earlier upstream PR
  (commit 4c264b8c) with zero constraint-system-specific content, and
  main has since evolved it considerably further.

Also removed two now-dead duplicates the merge surfaced without a
conflict marker (both branches had independently fixed the same
things): the OPTIONS/OP command dispatch/autocomplete entries, and
automation.rs's open_finalizes_and_purges_like_the_ui_open_path test
(kept main's version, which covers strictly more: solid_models/
material_base_dir reset on "new").

Full workspace suite passes (812 lib tests + this branch's own 24
constraint/persistence integration tests) except the one pre-existing,
unrelated font-test failure already present on main. Zero clippy
findings in the hand-written merge resolution itself; the ~1,171
warnings clippy reports are pre-existing in the 54 absorbed commits,
not introduced here.

Co-Authored-By: Claude Sonnet 5 <[email protected]>

src/app/view/mod.rs

@@ -2977,7 +2977,7 @@ pub(super) fn doc_tab_bar<'a>(
     let new_btn = button(text("+").size(14))
         .on_press(Message::TabNew)
         .height(iced::Length::Fixed(28.0))
-        .padding([5, 10])
+        .padding([4, 8])
         .style(|theme: &Theme, status| {
             let palette = theme.palette();
             let hovered = matches!(
@@ -3007,7 +3007,7 @@ pub(super) fn doc_tab_bar<'a>(
                 top: 0.0,
                 right: 0.0,
                 bottom: 0.0,
-                left: 6.0,
+                left: 2.0,
             })
             .into(),
     );

src/app/view/modal.rs

@@ -201,7 +201,14 @@ impl OpenCADStudio {
                         self.language,
                         self.options_tab,
                         self.cursor_size,
-                        self.pick_box,
+                        crate::ui::window::options::SelectionPrefs {
+                            pick_box: self.pick_box,
+                            pick_add: self.pick_add,
+                            pick_drag_rect: self.pick_drag_rect,
+                            grip_object_limit: self.grip_object_limit,
+                        },
+                        self.double_click_block_refedit,
+                        self.double_click_block_attedit,
                         self.cursor_type,
                         self.crosshair_color,
                         &self.crosshair_color_input,