Blocks palette: tabs, options, drag insertion and -INSERT

Rebuild the Blocks palette with Current Drawing / Recent / Favorites /
Libraries tabs, wildcard filter, six views, insertion options, click and
drop insertion and a block context menu. INSERT opens the palette, the
new -INSERT runs on the command line, the ribbon Insert button becomes a
block gallery, and BLOCKMRULIST, BLOCKREDEFINEMODE, BLOCKNAVIGATE,
BLOCKSTATE, EXPLMODE and INSNAME are added.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

src/app/commands/mod.rs

@@ -20,6 +20,7 @@ mod pc_extract;
 mod pdf_underlay;
 mod pdf_dialogs;
 mod xclip;
+mod blockvars;
 mod plotvars;
 mod styleprops;
 mod view;
@@ -296,6 +297,9 @@ impl OpenCADStudio {
         if let Some(t) = self.dispatch_plotvars(cmd, i) {
             return Some(t);
         }
+        if let Some(t) = self.dispatch_blockvars(cmd, i) {
+            return Some(t);
+        }
         if let Some(t) = self.dispatch_styleprops(cmd, i) {
             return Some(t);
         }
@@ -473,6 +477,14 @@ inventory::submit!(crate::command::CommandRegistration {
         // Block list + block-attribute list (command-line forms).
         "BLOCKPALETTE",
         "BLOCKSPALETTE",
+        "BLOCKSPALETTECLOSE",
+        "-INSERT",
+        "BLOCKMRULIST",
+        "BLOCKREDEFINEMODE",
+        "BLOCKNAVIGATE",
+        "BLOCKSTATE",
+        "EXPLMODE",
+        "INSNAME",
         "ATTMAN",
         "BATTMAN",
         // Drawing-content overview.