feat(block-editor): add authoring palette UI

Add a dockable Block Editor palette with selectable Parameters, Actions,
Parameter Sets and Constraints pages, reusing shared dock controls, icons
and ribbon-style hover bubbles.

Parameters, Actions, Parameter Sets and Block Properties Table are UI
catalogs only. Their entries remain disabled; this commit does not add
parameter placement, dynamic action behavior, parameter-set authoring or
block properties table functionality.

The Constraints page connects its geometric and dimensional entries to
existing ribbon commands. It reuses their implementations and adds no new
constraint behavior.

Keep the palette specific to BEDIT and retain its placement and selected
page across closing/reopening and Test Block. Opening, closing, switching
pages and clicking disabled entries preserve the document, undo history
and any running command.

Validation: 7 palette tests, 57 dock checks and 46 ribbon checks passed
(overlapping groups); rendered pages inspected and native debug build passed.

src/ui/window/mod.rs

@@ -3,6 +3,7 @@ pub mod alias_editor;
 pub mod annotation_data;
 pub mod attdef_dialog;
 pub mod attribute_editor;
+pub mod authoring_palettes;
 pub mod auto_constrain_settings;
 pub mod block_definition;
 pub mod block_edit_picker;