feat: node graph overlay; move to opencadcodec/opencadkernel/opencadgraph

The codec and kernel repositories and crates are renamed opencadcodec and
opencadkernel. Inside OCS they are depended on under short keys, so code
reads `codec::`, `kernel::` and the new `graph::` (opencadgraph, the node
graph engine). File-format and protocol spellings stay as they were: the
ACIS product id `acadrust`, the ACADRUST_* switches and the plugin
version keys `acadrust_version` / `acadrust_source`.

A button left of MCP on the command line opens a translucent node graph
over the viewport, with a palette of object, input, math, logic, list,
text and geometry nodes added by click or drag. An object node owns
drawing entities and its rows are the Properties panel's own rows for
them: the single-object page is extracted from refresh_properties as
entity_property_sections, values use the control protocol's
property_json, and writes go through set_property_value with a property
target override, so the panel, MCP and the graph share one read/write
path. A list reaching an object row makes one entity per element. Each
graph action is one undo step; the canvas pans and zooms.

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

src/modules/annotate/data_link.rs

@@ -4,8 +4,8 @@ use crate::command::{CadCommand, CmdResult, WorkingPlane};
 use crate::modules::{IconKind, ModuleEvent, ToolDef};
 use crate::scene::model::wire_model::WireModel;
 use crate::t;
-use acadrust::entities::Table;
-use acadrust::EntityType;
+use codec::entities::Table;
+use codec::EntityType;
 use glam::DVec3;
 
 pub const ICON: IconKind = IconKind::Svg(include_bytes!("../../../assets/icons/data_link.svg"));
@@ -38,8 +38,8 @@ impl DataLinkPlaceCommand {
     /// Place a table that references a data-link object already stored in the
     /// drawing. Every populated cell is locked and points at the same link so
     /// update and save/reopen keep one stable relationship.
-    pub fn existing(mut table: Table, link: acadrust::Handle) -> Self {
-        use acadrust::entities::table::CellStateFlags;
+    pub fn existing(mut table: Table, link: codec::Handle) -> Self {
+        use codec::entities::table::CellStateFlags;
         let rows = table.row_count() as i32;
         let columns = table.column_count() as i32;
         for row in &mut table.rows {
@@ -156,7 +156,7 @@ impl CadCommand for DataLinkPlaceCommand {
 
     fn on_point(&mut self, point: DVec3) -> CmdResult {
         let point = self.plane.to_local(point);
-        self.table.insertion_point = acadrust::types::Vector3::new(point.x, point.y, point.z);
+        self.table.insertion_point = codec::types::Vector3::new(point.x, point.y, point.z);
         CmdResult::CommitAndExit(
             self.plane
                 .place_entity(EntityType::Table(self.table.clone())),