Frames: state-following ribbon list, DWF/DGN frames, image frame encoding and profile, frame-only picking

- The Frames list shows the drawing's frame state (hide / display and plot /
  display but not plot / frames vary), follows commands, undo and document
  switches, and lists the mixed state as a disabled item.
- DWFFRAME and DGNFRAME are frame variables of their own, kept in the header,
  and FRAME sets them with the others.
- Out-of-range frame values say "Requires an integer between 0 and 2." and
  ask again; a set value reports "Regenerating model.".
- IMAGEFRAME is stored in the image variables as bits (2 is written as 3) and
  a drawing without them uses the profile value, which setting IMAGEFRAME
  updates and the settings file keeps.
- Raster images, PDF underlays and wipeouts are picked on their frame only;
  underlay snap geometry is never picked.

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

src/app/commands/mod.rs

@@ -618,6 +618,8 @@ inventory::submit!(crate::command::CommandRegistration {
         "FRAME",
         "IMAGEFRAME",
         "PDFFRAME",
+        "DWFFRAME",
+        "DGNFRAME",
         "PDFOSNAP",
         "UOSNAP",
         "PDFIMPORTMODE",
@@ -630,6 +632,7 @@ inventory::submit!(crate::command::CommandRegistration {
         "WIPEOUTFRAME",
         "FRAMES0",
         "FRAMES1",
+        "FRAMES3",
         "FRAMES2",
         "UOSNAP0",
         "UOSNAP1",

src/app/commands/styleprops.rs

@@ -10,6 +10,8 @@ impl OpenCADStudio {
             "FRAMES0" => return self.dispatch_styleprops("SETVAR FRAME 0", i),
             "FRAMES1" => return self.dispatch_styleprops("SETVAR FRAME 1", i),
             "FRAMES2" => return self.dispatch_styleprops("SETVAR FRAME 2", i),
+            // The mixed state is shown, never chosen.
+            "FRAMES3" => return Some(Task::none()),
             "UOSNAP0" => return self.dispatch_styleprops("SETVAR UOSNAP 0", i),
             "UOSNAP1" => return self.dispatch_styleprops("SETVAR UOSNAP 1", i),
             // COLOR <ByLayer|ByBlock|1-255|name> — the colour applied to new
@@ -1017,6 +1019,8 @@ impl OpenCADStudio {
                     | "FRAME"
                     | "IMAGEFRAME"
                     | "PDFFRAME"
+                    | "DWFFRAME"
+                    | "DGNFRAME"
                     | "PDFOSNAP"
                     | "UOSNAP"
                     | "PDFIMPORTMODE"
@@ -1283,13 +1287,23 @@ impl OpenCADStudio {
                                             self.tabs[i].scene.bump_entities(&changes);
                                         }
                                         self.tabs[i].dirty = true;
+                                        // IMAGEFRAME also lands in the profile.
+                                        self.save_config();
                                     }
                                     self.command_line
-                                        .push_output(&crate::tf!("{name} = {mode}"));
+                                        .push_output(crate::t!("Regenerating model.").as_ref());
+                                }
+                                // Out of range: say so and ask again.
+                                _ => {
+                                    self.command_line.push_error(
+                                        crate::t!("Requires an integer between 0 and 2.").as_ref(),
+                                    );
+                                    self.command_line.push_output(
+                                        crate::tf!("Enter new value for {name} <{current}>:")
+                                            .as_ref(),
+                                    );
+                                    self.pending_setvar = Some(name.clone());
                                 }
-                                _ => self.command_line.push_error(
-                                    crate::tf!("SETVAR: {name} requires 0, 1, or 2.").as_ref(),
-                                ),
                             },
                             None => {
                                 self.command_line.push_output(crate::tf!(