Section Analysis (FusionHalfSectionViewCommand, INSPECT): cut the view by an origin plane, construction plane or planar face with an offset (drag arrow) and flip; the inside of cut bodies shows a flat cap colour; live while the dialog is open, Remove Section on the right-click menu; viewport shader validated in a test

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AS5Tn3xieewUSg3uxrMVdL

crates/engine/src/cmd/mod.rs

@@ -12,6 +12,7 @@ pub use features::auto_operation;
 mod file;
 mod inspect;
 mod measure_sel;
+mod section;
 pub(crate) use measure_sel::measure_items;
 mod parameters;
 mod sketch;
@@ -129,6 +130,7 @@ pub fn command_specs() -> Vec<&'static CommandSpec> {
     v.extend(parameters::COMMANDS.iter());
     v.extend(file::COMMANDS.iter());
     v.extend(inspect::COMMANDS.iter());
+    v.extend(section::COMMANDS.iter());
     v
 }