Point clouds: attach dialog, crop toolbar, stylize, palette rows

POINTCLOUDATTACH opens the Attach Point Cloud dialog after the file is
chosen; its Attach button lives in the Attach Underlay list instead of a
separate Insert panel. A selected cloud brings the crop tools to the
right-edge toolbar. POINTCLOUDSTYLIZE sets the stylization with the
reference's prompts, the External References palette lists point clouds
(unload, reload, detach, path), and definitions keep the header extents.

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

src/ui/ribbon/context_tools.rs

@@ -59,6 +59,24 @@ pub fn pdf_underlay_tools(kind: codec::entities::UnderlayType) -> Vec<ToolDef> {
     tools
 }
 
+/// Point cloud tools: the three crops, showing, inverting and removing
+/// them, and the palette.
+pub fn point_cloud_tools() -> Vec<ToolDef> {
+    vec![
+        tool("_PCCROPRECT", "Rectangular\nCrop", CLIP),
+        tool("_PCCROPPOLY", "Polygonal\nCrop", CLIP),
+        tool("_PCCROPCIRC", "Circular\nCrop", CLIP),
+        tool(
+            "_PCCROPSHOW",
+            "Show\nCropping",
+            include_bytes!("../../../assets/icons/underlay_frames.svg"),
+        ),
+        tool("_PCCROPINVERT", "Invert\nCropping", CLIP),
+        tool("_PCUNCROP", "Remove All\nCropping", UNCLIP),
+        tool("EXTERNALREFERENCES", "External\nReferences", crate::ui::icons::FOLDER_OPEN),
+    ]
+}
+
 /// External reference tools: edit, open, clipping and the palette.
 pub fn xref_tools() -> Vec<ToolDef> {
     vec![
@@ -90,6 +108,15 @@ impl Ribbon {
         self.xref_ctx
     }
 
+    /// Only point clouds are selected: whether the first shows its crops.
+    pub fn set_point_cloud_context(&mut self, context: Option<bool>) {
+        self.point_cloud_ctx = context;
+    }
+
+    pub fn point_cloud_context(&self) -> Option<bool> {
+        self.point_cloud_ctx
+    }
+
     /// Select a tab by its module id.
     pub fn select_by_id(&mut self, id: &str) -> bool {
         match self.modules.iter().position(|m| m.id() == id) {

src/ui/ribbon/mod.rs

@@ -26,7 +26,7 @@ pub(crate) use draw_panel::tools as panel_tools;
 mod modify_panel;
 mod color_dropdown;
 mod context_tools;
-pub use context_tools::{pdf_underlay_tools, xref_tools, UnderlayContext};
+pub use context_tools::{pdf_underlay_tools, point_cloud_tools, xref_tools, UnderlayContext};
 use widgets::{StyleContext, *};
 pub(crate) use widgets::{REDO_HISTORY_ID, UNDO_HISTORY_ID};
 mod collapse;
@@ -109,6 +109,8 @@ pub struct Ribbon {
     underlay_ctx: Option<UnderlayContext>,
     /// Only xrefs are selected.
     xref_ctx: bool,
+    /// Only point clouds are selected: whether the first shows its crops.
+    point_cloud_ctx: Option<bool>,
     /// XDWGFADECTL as the Reference slide-out shows it (negative = off).
     pub xref_fade: i32,
 }
@@ -206,6 +208,7 @@ impl Ribbon {
             collapse_tight: Arc::new(AtomicBool::new(false)),
             underlay_ctx: None,
             xref_ctx: false,
+            point_cloud_ctx: None,
             xref_fade: 50,
         }
     }