feat(view): -VIEW orthographic UCS, sEttings and Window like the reference

An orthographic preset sets its orthographic UCS while UCSORTHO is on
(*FRONT*, *RIGHT*, …; TOP returns to the world UCS); presets no longer
flip to the opposite view when repeated. -VIEW runs as its own command:
Window asks for the name and corners, sEttings loops over Background,
Categorize, Layer snapshot, live Section, Ucs and Visual style with the
reference prompts and messages, Save keeps the UCS with the view while
UCSVIEW is on and Restore brings it back. UCSORTHO and UCSVIEW are
profile variables.

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

src/app/settings.rs

@@ -424,6 +424,10 @@ pub struct UserSettings {
     pub field_display: bool,
     /// SURFACEASSOCIATIVITY: new surfaces stay associative to their sources.
     pub surface_associativity: bool,
+    /// UCSORTHO: an orthographic view preset also sets its orthographic UCS.
+    pub ucs_ortho: bool,
+    /// UCSVIEW: a saved named view keeps the current UCS.
+    pub ucs_view: bool,
     /// Nested-copy symbol handling: false inserts, true binds.
     pub ncopy_bind: bool,
     /// Last Options page; unknown saved names fall back without rejecting the config.
@@ -838,6 +842,8 @@ impl Default for UserSettings {
             attdef_on_screen: true,
             field_display: true,
             surface_associativity: true,
+            ucs_ortho: true,
+            ucs_view: true,
             ncopy_bind: false,
             cursor_type: CursorType::Crosshair,
             crosshair_color: None,